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khc3
10-03-13, 13:47
Last time I gave serious thought to my choice of carry pistol, a few years ago, the height of the bore axis above the grip was being mentioned by some as a serious criteria to consider when choosing a pistol.

It also seemed a small, but vocal, group of dissenters would be on every discussion, discounting it as more important in theory than reality.

I don't seem to read much mention of it recently, but what is the current consensus?

jondoe297
10-03-13, 13:52
It's a minor, almost irrelevant factor to me. I can shoot a SIG with it's mountainous bore axis height as well as I can a Glock.

Alaskapopo
10-03-13, 13:57
Last time I gave serious thought to my choice of carry pistol, a few years ago, the height of the bore axis above the grip was being mentioned by some as a serious criteria to consider when choosing a pistol.

It also seemed a small, but vocal, group of dissenters would be on every discussion, discounting it as more important in theory than reality.

I don't seem to read much mention of it recently, but what is the current consensus?

Its physics not a myth.
Pat

khc3
10-03-13, 14:02
Its physics not a myth.
Pat

OK, tell me more.

ASH556
10-03-13, 14:06
"shooting it well" has to be defined. Will bore axis affect accuracy? It shouldn't. Will it affect your ability to get the gun back on target for follow-up shots? You betcha. Basic physics:

F=MV (force = mass * velocity). If there is a greater mass above the bore axis (as there is with a Sig compared to a Glock for example) then given an equal slide velocity, there will be a greater recoil force with the gun that has a higher bore axis.

There is some torque that plays into the equation as well based on the pivot point created by your hand but bottom line is a higher bore axis leads to more felt recoil and slower follow-up shots. It can be trained around, but it is a factor.

Alaskapopo
10-03-13, 14:08
OK, tell me more.

The higher up the bore is the more leverage it has over your hand to flip the gun backwards. Recoil forces both send the gun back and the muzzle up. The higher your grip the more the gun recoils straight back which allows for faster recovery between shots. Most of the people calling this a myth are those who have not yet developed the skills to shoot fast. You are not going to notice it as much in slow fire.
Pat

Kchen986
10-03-13, 14:16
After shooting a Steyr M9 immediately followed by a Glock 19 I can tell you its not a myth, but still only one factor among many when picking a pistol.

warpedcamshaft
10-03-13, 14:27
I will ask you to please narrow the question...

Are you asking if a higher bore axis negatively impacts performance when firing at higher speed or the perceived recoil characteristics of a handgun?

Experience has taught me that these two questions/characteristics are not always directly proportional.

DanjojoUSMC
10-03-13, 14:37
"shooting it well" has to be defined. Will bore axis affect accuracy? It shouldn't. Will it affect your ability to get the gun back on target for follow-up shots? You betcha. Basic physics:

F=MV (force = mass * velocity). If there is a greater mass above the bore axis (as there is with a Sig compared to a Glock for example) then given an equal slide velocity, there will be a greater recoil force with the gun that has a higher bore axis.

There is some torque that plays into the equation as well based on the pivot point created by your hand but bottom line is a higher bore axis leads to more felt recoil and slower follow-up shots. It can be trained around, but it is a factor.

Recoil characteristics, not recoil itself. A Sig 226 will have a more jumpy muzzle than a G17 but it has less recoil.

If you got the timing down right and the pistol is sprung well then the bore axis doesn't mean much unless you are machine gunning at spitting distance.

Failure2Stop
10-03-13, 14:38
The higher up the bore is the more leverage it has over your hand to flip the gun backwards. Recoil forces both send the gun back and the muzzle up. The higher your grip the more the gun recoils straight back which allows for faster recovery between shots. Most of the people calling this a myth are those who have not yet developed the skills to shoot fast. You are not going to notice it as much in slow fire.
Pat

I used to buy into the bore axis argument.
I have since revised my position, in that in actual performance the minor difference in bore height does not seem to really make much difference, whereas shooter training level, sights, and competence with a particular gun matters the most.

There is also the issue of gun weight and reciprocating mass that effects muzzle flip/sight tracking.

Another interesting aspect; what a lot of people thing of as low bore axis are higher than they think, and guns that are at the top of the competitive pile aren't all that low.

http://www.dawsonprecision.com/images/519-Edge%2040%20ST%20HC.jpg
STI

Compare to:

http://upload.wikimedia.org/wikipedia/commons/thumb/2/2c/Koalorka_H%26K_P30L.jpg/300px-Koalorka_H%26K_P30L.jpg

http://www.hyattgunstore.com/images/P/main-6374.jpg

http://www.imfdb.org/images/thumb/d/dc/Beretta-92FS-Vertec-SS.jpg/400px-Beretta-92FS-Vertec-SS.jpg

http://www.guns.com/wp-content/uploads/2012/12/Glock22-gen41.jpg

http://www.imfdb.org/images/thumb/4/44/S%26W_M%26P_9mm.jpg/400px-S%26W_M%26P_9mm.jpg

To make me concerned about bore axis would require a distinct departure from contemporary design.

khc3
10-03-13, 14:48
I guess I am looking for two things: how much the physics of it matter with real-world examples, ie. has one gun been proven to be harder/slower to shoot than others for a majority of shooters because of high bore axis, and, has anyone here made a personal choice of handgun due to issues that he related directly to high bore axis?

ETA: I have been shooting a P2000 9mm lately, after a couple years of shooting a G19. It felt slower with more muzzle flip at first, but I think that was due more to grip angle than bore axis. Now that I've been shooting it for a little while and have gotten more comfortable with the grip (and the LEM), I think I shoot it faster than the glock.

SpeedRacer
10-03-13, 15:01
Bore axis, while relevant, is just one of many, many factors that affect a gun's movement during recoil and "shootability". It's far from a decision maker IMO.

ASH556
10-03-13, 15:02
I guess I am looking for two things: how much the physics of it matter with real-world examples, ie. has one gun been proven to be harder/slower to shoot than others for a majority of shooters because of high bore axis, and, has anyone here made a personal choice of handgun due to issues that he related directly to high bore axis?

ETA: I have been shooting a P2000 9mm lately, after a couple years of shooting a G19. It felt slower with more muzzle flip at first, but I think that was due more to grip angle than bore axis. Now that I've been shooting it for a little while and have gotten more comfortable with the grip (and the LEM), I think I shoot it faster than the glock.
No. Bore axis should not be a significant enough issue to choose on alone. In fact, availability of parts, magazines, and holsters eliminates everything but a Glock, M&P, Sig, and Beretta for me. I prefer strikers to a DA/SA hammer gun so that puts me back at Glock & M&P. I like the M&P ergo's better than the Glock's so the situation solves itself through logic. What I "shoot better" is irrelevant if I can't support the platform.

jyo
10-03-13, 15:18
Yeah, for YEARS I've heard about those terrible HKs and their high-bore axis---horrible(!)---and yet my HKs are some of the softest shooting pistols there are---and I've shot many many...
So, is it relevant? Maybe---does it matter? Not a great deal.

lunchbox
10-03-13, 15:21
"shooting it well" has to be defined. Will bore axis affect accuracy? It shouldn't. Will it affect your ability to get the gun back on target for follow-up shots? You betcha. Basic physics:

F=MV (force = mass * velocity). If there is a greater mass above the bore axis (as there is with a Sig compared to a Glock for example) then given an equal slide velocity, there will be a greater recoil force with the gun that has a higher bore axis.

There is some torque that plays into the equation as well based on the pivot point created by your hand but bottom line is a higher bore axis leads to more felt recoil and slower follow-up shots. It can be trained around, but it is a factor.Damn now I'm interested. Does caliber make difference? Would barrel length play into effect? Say a shorter barrel with less mass, closer to hand VS longer barrel with more mass on end? Just tryn to wrap head around.

Failure2Stop
10-03-13, 15:27
Damn now I'm interested. Does caliber make difference? Would barrel length play into effect? Say a shorter barrel with less mass, closer to hand VS longer barrel with more mass on end? Just tryn to wrap head around.

Very popular gun in open was a short 1911/STI slide w/comp.
Less reciprocating mass, faster return to battery, finely tuned ammo to provide sufficient gas to give stability while making major, optics make sight radius irrelevant.

Caliber most certainly makes a difference, as does many other factors. Even frame material makes a little bit of difference.

ASH556
10-03-13, 15:28
Damn now I'm interested. Does caliber make difference? Would barrel length play into effect? Say a shorter barrel with less mass, closer to hand VS longer barrel with more mass on end? Just tryn to wrap head around.

hmmm...not sure if you're serious. Based on your location, are you an Auburn ME trying to show up a GT guy?

steyrman13
10-03-13, 15:28
To bring another point to the table--
Has anyone shot the new Chiappa Rhino revolver? I shot one at SHOT this past year in .357 Mag. The recoil is "different.' Although it may not flip the muzzle as much, it puts more of the force in the palm. I don't know if it was just the ergonomics of the grip, but it felt as "bad" as shooting as M&P340 Scandium frame 357 Mag. Like a Hammer smacking your hand on concrete.

The steyr M9 is one of the best examples of the low bore axis. It does prevent the muzzle flip more so than a Sig, but it isn't enough of a difference to go for it over a Glock or M&P due to availability to find parts and holsters and mags, etc.

warpedcamshaft
10-03-13, 16:10
I remembered reading a post by Mr. Bruce Gray regarding bore axis. Given his experience and accomplishments, I believe his thoughts are worth considering.

Search for "Bruce Gray HK Bore Axis question."

That is a great article from someone with a lot of experience winning using pistols with a high bore axis.

He mentions removing the recoil spring buffer in the full-sized USP in order to change the recoil characteristics for limited class!

C4IGrant
10-03-13, 16:14
Last time I gave serious thought to my choice of carry pistol, a few years ago, the height of the bore axis above the grip was being mentioned by some as a serious criteria to consider when choosing a pistol.

It also seemed a small, but vocal, group of dissenters would be on every discussion, discounting it as more important in theory than reality.

I don't seem to read much mention of it recently, but what is the current consensus?

People go by feel (which is misleading). From my experience with comparing a PPQ or HK to a Glock (the flattest shooting pistol out there), there is very little difference in splits. On top of this, using split times to choose a gun is silly.

Read SPQR's comments here as he switched from Glock to HK: https://www.m4carbine.net/showthread.php?t=138319&highlight=hk&page=5


C4

montrala
10-03-13, 16:16
F=MV (force = mass * velocity). If there is a greater mass above the bore axis (as there is with a Sig compared to a Glock for example) then given an equal slide velocity, there will be a greater recoil force with the gun that has a higher bore axis.

There is some torque that plays into the equation as well based on the pivot point created by your hand but bottom line is a higher bore axis leads to more felt recoil and slower follow-up shots. It can be trained around, but it is a factor.

We should not forget that same mass that was traveling backward, then travels forward (at different velocity and actually greater mass, because if feeds complete round forward). Bore axis is also often measured in relation to top of the hand. Good way to compare different pistols, but what is actually relevant is distance to pivot point you mentioned. This pivot point usually is wrist. This makes bore axis height differences proportionally less. That is why bore axis itself is more less irrelevant (unless we start to talk about some abominations that for sure do exist). What is relevant, to fast shooting at least, is how complete cycle works.

In IPSC competition shooting we call it tracking and refer to front sight movement under recoil. It is important for front sight to return after complete cycle to same point it was before shot. Preferably as fast as possible and without vertical oscillation. In competition this is achieved by tuning load and spring rates. To make things happen as fast as possible it is better to have pistol with higher cyclic rate. So shorter slides, slide porting etc. Also heavy frames, long dust covers, tungsten recoil guides or heavy magwells help some people to improve tracking, by adding more inertia to the system. But good shooters, who manage recoil prefer lighter guns, that are easier and faster to do target transitions. But there is a trade off - faster slide velocities reduce reliability or make guns very ammo sensitive. That is why service pistols can only marginally benefit from this experience to achieve desired reliability.

As mentioned before, top race guns are based either on 1911/STI/SV design or CZ-75 design. Both have relatively high bore axis, compared to striker fired pistols like Glock, S&W or Steyr, but easily can be shot as fast or faster.

Usual suspect for bore axis height theory fans is HK USP, because it is very hard to shoot fast. This is flawed example, because bore axis height is same as 1911. Source or "problem" (or feature) of HK USP is very complicated, floating recoil system (that during shot works in very different way that when hand cycling so lot of people have problem to understand how it works). This recoil system does two things. First it slows slide velocity significantly. This makes gun shooting softer (less felt recoil) and work more reliable. Second thing is that is has 3 stage of work for recoil system on recoil and 2 stages on return to battery. This makes tracking inconsistent. Other HK designs (USPc, P2000, P30/L, HK45, HK45C) have same bore axis height, but "classic" recoil system and can be shot much faster than USP.

Bottom line for everybody: Get some ammo. Preferably lots of ammo. Get shot timer. Hit the range. Find what work best. Have fun. :D

lunchbox
10-03-13, 16:16
Very popular gun in open was a short 1911/STI slide w/comp.
Less reciprocating mass, faster return to battery, finely tuned ammo to provide sufficient gas to give stability while making major, optics make sight radius irrelevant.

Caliber most certainly makes a difference, as does many other factors. Even frame material makes a little bit of difference. Kinda figured multiple factors at play, probably the biggest being the shooter. Thanks for explanation.


hmmm...not sure if you're serious. Based on your location, are you an Auburn ME trying to show up a GT guy?Why I would never pull a Virginia Tech on Ya' :D:D JK Couldn't afford AU, so tech program at community college is what my broke ass got:p.

Arctic1
10-03-13, 16:18
Here is a comparative video showing the muzzle flip of different handguns:

http://youtube.com/watch?v=WOirbcsCQ1o

It is by no means definitive, and it is biased as hell being a promotional video for the Strike One, but it does support a few observations made by a few people in this thread:

-height of boreline over grip alone will not define recoil characteristics of a handgun; ie amount of muzzle flip.

-several factors of a handgun design will affect how it recoils

In my opinion, the difference between a gun with a low boreline and a high borline, is how it presents naturally or not. For me, a gun with a low boreline feels more natural when I present it. Experienced this many years ago when I shot a USP for the first time, only having shot a Glock 17 previously(issued sidearm). Still, most likely a training issue.

Lastly, when discussing recoil it is important to use the correct terms when describing what happens.

ETA: Also, semi-auto handgun recoil will be different than a revolver or rifle, due to the exaggerated center of gravity shift when the slide cycles to the rear.

Meplat
10-03-13, 16:24
The day somebody can prove to me that the specific and exact reason someone lost a shoot out was because their bore axis was too high, I'll take every gun I have with a "high bore axis" and donate them to Dianne Feinstein to dispose of as she sees fit.

Until then, it's mallninja talk obsessing over and nitpicking minute details instead of training and finding what works and what doesn't.

jondoe297
10-03-13, 16:56
I used to buy into the bore axis argument.
I have since revised my position, in that in actual performance the minor difference in bore height does not seem to really make much difference, whereas shooter training level, sights, and competence with a particular gun matters the most.



I can't really sum up how I feel on the matter any better than that.

glocktogo
10-03-13, 17:09
We should not forget that same mass that was traveling backward, then travels forward (at different velocity and actually greater mass, because if feeds complete round forward). Bore axis is also often measured in relation to top of the hand. Good way to compare different pistols, but what is actually relevant is distance to pivot point you mentioned. This pivot point usually is wrist. This makes bore axis height differences proportionally less. That is why bore axis itself is more less irrelevant (unless we start to talk about some abominations that for sure do exist). What is relevant, to fast shooting at least, is how complete cycle works.

In IPSC competition shooting we call it tracking and refer to front sight movement under recoil. It is important for front sight to return after complete cycle to same point it was before shot. Preferably as fast as possible and without vertical oscillation. In competition this is achieved by tuning load and spring rates. To make things happen as fast as possible it is better to have pistol with higher cyclic rate. So shorter slides, slide porting etc. Also heavy frames, long dust covers, tungsten recoil guides or heavy magwells help some people to improve tracking, by adding more inertia to the system. But good shooters, who manage recoil prefer lighter guns, that are easier and faster to do target transitions. But there is a trade off - faster slide velocities reduce reliability or make guns very ammo sensitive. That is why service pistols can only marginally benefit from this experience to achieve desired reliability.

As mentioned before, top race guns are based either on 1911/STI/SV design or CZ-75 design. Both have relatively high bore axis, compared to striker fired pistols like Glock, S&W or Steyr, but easily can be shot as fast or faster.

Usual suspect for bore axis height theory fans is HK USP, because it is very hard to shoot fast. This is flawed example, because bore axis height is same as 1911. Source or "problem" (or feature) of HK USP is very complicated, floating recoil system (that during shot works in very different way that when hand cycling so lot of people have problem to understand how it works). This recoil system does two things. First it slows slide velocity significantly. This makes gun shooting softer (less felt recoil) and work more reliable. Second thing is that is has 3 stage of work for recoil system on recoil and 2 stages on return to battery. This makes tracking inconsistent. Other HK designs (USPc, P2000, P30/L, HK45, HK45C) have same bore axis height, but "classic" recoil system and can be shot much faster than USP.

Bottom line for everybody: Get some ammo. Preferably lots of ammo. Get shot timer. Hit the range. Find what work best. Have fun. :D

This is the best post in the thread. There is so much more at work than just bore axis. One thing not mentioned yet is chamber pressure at the millisecond the barrel unlocks from the slide. This has a significant impact on slide velocity, which is a significant factor is sight lift.

It's really pretty irrelevant when shooting splits at 7 yards. Shoot splits at 15 yards and it becomes much more relevant. The more you push the practical envelope of the pistol, the greater the impact sight lift has on shooting fast, accurately. Another part of the equation is shooter skill level. Somone with average to poor eyesight is going to have a much more difficult time discerning the difference. If you have trained and capable eyes that can actually track sight lift, less is more.

You can shoot as fast as you can pull the trigger. However, unless you're point shooting you can only hit as fast as you can see to align the sights. At that skill level, bore axis is a relevant factor.

The Dumb Gun Collector
10-03-13, 17:13
Just add my +1 to anything Montrala says

ruchik
10-03-13, 19:15
I am of the opinion that bore axis doesn't really matter unless/until you're good enough to where it DOES make a difference. And if you get to that point, then I'm fairly sure you'll know your weapon well enough to where it just won't matter anymore at all.

YVK
10-03-13, 19:15
We should not forget that same mass that was traveling backward, then travels forward

This little fact is conveniently forgotten by proponents of "physics" theory. If one is going to assume that slide has more effective leverage to flip muzzle up during rearward motion, then one has to accept the slide has same extra leverage to bring muzzle down when returning to battery.
Until somebody figures out how to objectively measure time of muzzle up-and-down, I'd rely on something more tangible. Like tons of open minded shooters not giving a damn about bore axis.

SigSlave
10-03-13, 19:33
Deleted.

Texaspoff
10-03-13, 20:03
High bore axis...the new catch phrase to replace limp wristing as the cause for not hitting a target and FTE...:sarcastic:


I don't gravitate towards or away from a particular firearms platform because of it's bore axis. If a platform works for me then it works for me, I could care less about bore axis.

Just my two cents.

TXPO

Alaskapopo
10-03-13, 20:13
This little fact is conveniently forgotten by proponents of "physics" theory. If one is going to assume that slide has more effective leverage to flip muzzle up during rearward motion, then one has to accept the slide has same extra leverage to bring muzzle down when returning to battery.
Until somebody figures out how to objectively measure time of muzzle up-and-down, I'd rely on something more tangible. Like tons of open minded shooters not giving a damn about bore axis.

Not forgotten but not relevant either. Its not going to bring the muzzle down faster than the gun with a lower bore axis that did not move up as high in the first place. The magnified up and down motion of the muzzle is harder to control vs. a strait back recoil impulse hence by my comped open pistol is easier to fire fast. You want the gun to remain as flat as possible.
Pat

Texaspoff
10-03-13, 21:38
Check out this guy at time 4:50 and his triple taps, he seems to be shooting the PPQ pretty flat. :)


http://www.youtube.com/watch?v=sJaJmNPJpf8&feature=share&list=PLA0WvhDPaJDey_6uD8mZ18L-ujrxtis_A

Alaskapopo
10-03-13, 21:43
Check out this guy at time 4:50 and his triple taps, he seems to be shooting the PPQ pretty flat. :)


http://www.youtube.com/watch?v=sJaJmNPJpf8&feature=share&list=PLA0WvhDPaJDey_6uD8mZ18L-ujrxtis_A

That means nothing without a comparison video of the same shooter with a Glock 19 with the same ammo. I have shot both and there is a difference. Perhaps I will do a video on it time permitting. Also the video sucked. Perhaps he could get even further away form the camera and even closer to the target. LOL!:blink:
Pat

decodeddiesel
10-03-13, 22:01
"shooting it well" has to be defined. Will bore axis affect accuracy? It shouldn't. Will it affect your ability to get the gun back on target for follow-up shots? You betcha. Basic physics:

F=MV (force = mass * velocity). If there is a greater mass above the bore axis (as there is with a Sig compared to a Glock for example) then given an equal slide velocity, there will be a greater recoil force with the gun that has a higher bore axis.

There is some torque that plays into the equation as well based on the pivot point created by your hand but bottom line is a higher bore axis leads to more felt recoil and slower follow-up shots. It can be trained around, but it is a factor.

No, it's not.

F = mass * acceleration, aka Newton's 2nd. Velocity and acceleration are two different things.

I feel as though I am qualified to comment on this, however it has been a ball buster of a day so I may not make any sense.

To properly analyze what is going on during a recoil sequence of weapon (or for that matter any kinematic analysis) the first step is a free body diagram. After properly analyzing constraints and forces, only then can one identify what is actually going on.

Prior to the barrel unlocking, where no spring force is considered and neglecting the effects of gravity, the constraint would be your wrist and the axis of the force (F=ma) is the bore axis. The muzzle "flip" in a pistol is the result of what we call a "moment" generated by the difference in vertical height between your wrist and the bore axis. A moment is a force applied at a distance from a constraint. This is also known as torque, i.e. ft*lbs (foot pounds) or N*m (Newton meters). The moment acting on the system is directly proportional to the distance, or "lever arm". This is the reason why the .357 Chiappa revolver (http://www.youtube.com/watch?v=hR8_eY-HVJw) has so little muzzle flip. The axis of the force is directly in line with the hinge of your wrist and therefore the lever arm is effectively zero.

The "offset mass" or whatever has virtually nothing to do with it.

In all honesty however, the actual difference in height over bore between virtually all semi-auto pistols are so minor that the effect on muzzle flip is really minimal. Proper grip, stance, form, etc. obviously have a much greater effect. The Chiappa is unique because the difference in the bore axis between it and a traditional small frame revolver are huge.

ETA: Once the action unlocks and the slide begins it's rearward movement, the whole situation changes. However the primary upset in the sight picture, weapon orientation, etc. occurs prior to the barrel unlocking from the slide.

wake.joe
10-03-13, 22:03
While I do shoot a glock; I have found by experience that the bore-axis argument is generally made by overweight do-nothings with a shallow well of handgun experience. A great theory on paper, at best. Irrelevant in use.

Perhaps a little harsh. I'm just tired of hearing the same gun "Facts" over and over.

YVK
10-03-13, 22:05
Its not going to bring the muzzle down faster than the gun with a lower bore axis

This is your opinion, but it is not a fact. You have to measure up and down time to make it a fact. The only fact here is that the same extra leverage that's exists when slide is moving back is still present and works in opposite way when gun fully cycles. Whether you call it relevant or not doesn't change it; when things are different because the object moves with stronger leverage, they can't be different in one direction but not another.


You want the gun to remain as flat as possible.
Pat

Nope. I want my gun to come back as fast as possible. I don't care how high it flips when it cycles, as long as return is fast and repeatable.

Alaskapopo
10-03-13, 22:09
This is your opinion, but it is not a fact. You have to measure up and down time. The only fact here is that the same extra leverage that's exists when slide is moving back is still present and works in opposite way when gun fully cycles. Whether you call it relevant or not doesn't change it; when things are different because the object moves with stronger leverage, they can't be different in one direction but not another.



Nope. I want my gun to come back as fast as possible. I don't care how high it flips when it cycles, as long as return is fast and repeatable.

Physics is a science not an opinion. The higher up the muzzle goes the more it will have to travel to come back down. There is a reason your top shooters don't use guns with a high bore axis.
Pat

jondoe297
10-03-13, 22:25
Physics is a science not an opinion. The higher up the muzzle goes the more it will have to travel to come back down. There is a reason your top shooters don't use guns with a high bore axis.
Pat

Up and down aren't the only factors in the physics equation here. Cycle speed of the weapon plays heavily here.

BioLayne
10-03-13, 22:30
Last time I gave serious thought to my choice of carry pistol, a few years ago, the height of the bore axis above the grip was being mentioned by some as a serious criteria to consider when choosing a pistol.

It also seemed a small, but vocal, group of dissenters would be on every discussion, discounting it as more important in theory than reality.

I don't seem to read much mention of it recently, but what is the current consensus?

I shoot mostly glocks. I shout a p226 the other day and while it shot very 'soft' in terms of felt recoil, it had noticeably more muzzle flip to me.

My experience anyway.

MrCleanOK
10-03-13, 22:36
F=MV (force = mass * velocity). If there is a greater mass above the bore axis (as there is with a Sig compared to a Glock for example) then given an equal slide velocity, there will be a greater recoil force with the gun that has a higher bore axis.

There is some torque that plays into the equation as well based on the pivot point created by your hand but bottom line is a higher bore axis leads to more felt recoil and slower follow-up shots. It can be trained around, but it is a factor.

Not to nit pick, but Newton's second law of motion gives us:

Force = mass * acceleration

Mass * velocity is momentum.

YVK
10-03-13, 22:39
Pat, finally you and I agree on something: it is a science, not opinion. Now, if you could explain how distance traveled is more important than time of muzzle return, I'd feel enlightened.

BTW, comps work not only by reducing a flip, but by producing extra force to bring muzzle down faster. If you ever shot an overcomped gun, you could see muzzle dip down below the line of sight.

Montrala covered bore axis of competition guns above, HK vs 1911 example etc. Check out how Max Michel is doing with Sig 226.

DreadPirateMoyer
10-03-13, 22:47
This is also known as torque, i.e. ft*lbs (foot pounds) or N*m (Newton meters). The moment acting on the system is directly proportional to the distance, or "lever arm".

If we're going to be nitpicky on engineering here, torque and moment aren't the same thing. Torque is something that causes a change in angular momentum (causes something to move, like a driveshaft in a car), whereas moment does not (like placing a weight on a beam, which stops moving after deflection); heck, civil engineers break it down even farther than that, with torques causing twists and moments causing bends. Physicists use the term torque for everything, but that's because they're stupid and don't work in the real world where torque/moment are actually very different phenomena. :sarcastic: In this case, since there is a change in angular momentum, we're discussing torque.

And to get back to the OP's question, this is only one of many, many things to consider when discussing a gun's recoil characteristics. Sure, two completely identical guns only separated by their difference in bore axis will show that the one with the higher bore axis will have greater felt recoil, but as far as I know, no manufacturer makes two completely identical guns only differentiated by their bore axes. Bore axis generally only varies across brands and not within them, so it's not a good way to decide on how your gun's recoil characteristics will play out; other things also come into play, like the mass of the slide, single or dual recoil springs, recoil spring strength, recoil buffers, total weight of the gun, weight distribution (fore or aft), and a ton of other things. It's, unfortunately, not just simple physics. It's really complicated physics.

Because there are so many variables, the only real way to tell how a gun's recoil characteristics will play out is to shoot them, preferably in a controlled way that takes out any other variables (some sort of contraption that holds the gun sans human input would be great). I say this because there are plenty of guns out there that have higher bore axes but still have softer recoil than other guns with lower bore axes due to other variables in their design (HK45 is a good example, in my experience; shoots softer than some other .45s with lower bore axes).

Don't use bore axis as your only determining factor for predicting how a gun will fire in your hands. It's only one factor of many, albeit an (arguably) important one.

Alaskapopo
10-03-13, 23:22
Up and down aren't the only factors in the physics equation here. Cycle speed of the weapon plays heavily here.

Not as much as you would think.
Pat

Alaskapopo
10-03-13, 23:23
Pat, finally you and I agree on something: it is a science, not opinion. Now, if you could explain how distance traveled is more important than time of muzzle return, I'd feel enlightened.

BTW, comps work not only by reducing a flip, but by producing extra force to bring muzzle down faster. If you ever shot an overcomped gun, you could see muzzle dip down below the line of sight.

Montrala covered bore axis of competition guns above, HK vs 1911 example etc. Check out how Max Michel is doing with Sig 226.

Less distance less time. No offense but that is kind of like Duh. Also 99.999999% of the pros are not using HK's or Sigs.
Pat

opmike
10-03-13, 23:47
F=MV (force = mass * velocity). If there is a greater mass above the bore axis (as there is with a Sig compared to a Glock for example) then given an equal slide velocity, there will be a greater recoil force with the gun that has a higher bore axis.

I must quibble ;)

F = ma

P = mv

Where F equals force, m equals mass, a equals acceleration, P equals momentum, and v equals velocity. Multiplying mv (mass * velocity) doesn't give you units of force.

beschatten
10-04-13, 00:13
If I may, I would like to throw in a few comments in regards to the thread. Instead of solely relying on F=M*A and other simpleton equations that are used only in a vacuum scenario, let's take a look at what's really going on.

Theoretically, yes a lower bore axis equates to less muzzle flip as the slide travels rearward. The reason is because the gun pivots on tang of the gun where the shooter holds it. The higher up it is, the less travel it can have. However, people are missing a critical factor, friction.

In real-world applications, not everyone will have the same grip, have the same hands, apply an equal amount of pressure. Nothing is constant. The same goes for guns--there are no constants between manufactures, especially with the friction coefficient of the surfaces. It's impossible to compare a Sig 226 to a Glock in terms of felt recoil because of friction-whether that's from the shooter's side or on the guns. If the coefficient of friction (measured in Newtons) of a Glock 17 AT the tang was equivalent to the Sig 226, and they both had the same weight, the same springs, and the same loads, the Glock 17 would have less muzzle rise/flip. However, real-life doesn't permit that.

I mention friction because if there was, let's say a friction coefficient of 100 between the beavertail/tang of the gun and the web of your hand, the muzzle rise would be significantly less than 10 Newtons (given that the constants are the same between the two scenarios). The reason is that it takes more force (Newtons), for the gun to rotate on the web of the hand. So the energy that is expended as the bullet exits the gun, and the slide travels backwards, is wasted trying to overcome the friction coefficients.

So if you really want to reduce muzzle rise, stipple/checker the shit out of that tang/beavertail. Also, wear very, very, grippy tactical gloves. Sure, it may be ugly as sin having 20 LPI checkered beavertails on a 1911 or having grip tape on it, but it will work.

Next topic is the creating isometric tension with the hands. If you could clamp a gun, and apply a lot of force on the tang/beavertail with your strong hand, and the same amount of force rearwards with your weakhand, you will significantly reduce muzzle flip. This works on many different factors, but essentially, the gun wastes more energy fighting that tension. If you could create a vice of some sort and apply about 5000 Newtons of force in an isometric setting, once again, the gun would not move (if it doesn't break).

Now put isometric tension with a high friction coefficient at the tang of the gun and the gun will really be fighting to have any muzzle rise.

So what's my point? Every bodies experience with a gun's muzzle rise will be different. Every gun will have a different characteristic as well since friction coefficients of the surface at the tang, the weight of the gun, the barrel, the spring ect. is different. There are too many factors in play to calculate muzzle flip of gun A vs gun B. And if you want to reduce muzzle flip, you have a pretty good idea on how to do it too.

If you want to know if a lower borer axis does what its suppose to do, well that depends on all the other things that must be taken into account.

Texaspoff
10-04-13, 01:19
That means nothing without a comparison video of the same shooter with a Glock 19 with the same ammo. I have shot both and there is a difference. Perhaps I will do a video on it time permitting. Also the video sucked. Perhaps he could get even further away form the camera and even closer to the target. LOL!:blink:
Pat


Agreed the video isn't all that great. I'm just saying the guy is doing a pretty good job of controlling recoil on the PPQ. I'm sure he could do the same with a Glock.

I have PPQs and Glocks both and yes there is a difference in felt recoil between the two. I can also run both platforms ,same drills and score the same hits with either in about the same times. The PPQ and Glock both perform equally well for me. Not saying bore axis doesn't make a difference, I just choose not to worry about it.

Been carrying various pistols on/off duty for almost 20 years and bore axis didn't bother me when I carried Sigs in the 90's, I'm not going start worrying about it now.

In a high stress SHTF situation, bore axis isn't going to effect much when you gorilla fist your pistol. Just like that 8 pound trigger your not going to notice.

TXPO

YVK
10-04-13, 01:35
Less distance less time. No offense but that is kind of like Duh.

It is only duh is speed of return is equal. Which isn't because moving slide mass has more leverage on its way back into a battery with high axis guns.

Alaskapopo
10-04-13, 01:44
It is only duh is speed of return is equal. Which isn't because moving slide mass has more leverage on its way back into a battery with high axis guns.

Actually its the opposite. Since the gun has more leverage on the shooter and the gun moves more the slide actually returns slower. Its like the difference if you could hold the gun completely still and holding it like a fish.
Pat

Alaskapopo
10-04-13, 01:45
Agreed the video isn't all that great. I'm just saying the guy is doing a pretty good job of controlling recoil on the PPQ. I'm sure he could do the same with a Glock.

I have PPQs and Glocks both and yes there is a difference in felt recoil between the two. I can also run both platforms ,same drills and score the same hits with either in about the same times. The PPQ and Glock both perform equally well for me. Not saying bore axis doesn't make a difference, I just choose not to worry about it.

Been carrying various pistols on/off duty for almost 20 years and bore axis didn't bother me when I carried Sigs in the 90's, I'm not going start worrying about it now.

In a high stress SHTF situation, bore axis isn't going to effect much when you gorilla fist your pistol. Just like that 8 pound trigger your not going to notice.

TXPO
I too have carried HK's and Sigs over my 14 years as a LEO and I am not saying its the end all be all in selecting a sidearm. But it is a factor and its not a myth.
Pat

Arctic1
10-04-13, 02:02
I posted this on another board previously.

I will preface this by saying that I am not a physicist or a ballistician, nor I am particlarly intelligent, so what I present is a laymans understanding of recoil. I did not invent these findings, and what I write is taken from existing sources.

I have spent some time learning the physics behind it, talking to physicists who have explained the math behind it.

With that out of the way, here is the theory behind recoil.
-----------------------

There are 3 types of recoil:

1. Primary recoil
2. Secondary recoil
3. Felt recoil

Primary recoil is result of the momentum of the projectile and propellant moving in one direction (forward) and the gun moving in the other direction (backwards). This is not the main recoil felt, but it is noticeable. It stays the same unless weapon mass is increased or reduced, projectile mass is increased or reduced, or projectile velocity is increased or reduced. This is covered by Newton's Third Law of Motion.

Secondary recoil is when the hot expanding gases exit the muzzle after the projectile, causing the muzzle to recoil like a rocket. This is what contributes to muzzle rise, among other things. The effects of secondary recoil is the main recoil experienced when shooting, and is increased when shooting rapid follow up shots. It can be compensated for by proper weapon design, shooting stance/grip and muzzle devices.

Felt recoil is how the shooter preceives the recoil of a fire arm. It is related to the acceleration of the gun when discharged. A heavy gun will have slower acceleration, and results in the shooter perceiving the recoil as more pleasant. Recoil is commonly desribed as soft or sharp; a soft recoiling firearm has the recoil energy spread over a longer period of time, slow acceleration, and a sharper recoiling weapon has recoil spread over a shorter period of time, high acceleration.

The reciprocating parts of the firearm also affect felt recoil. A rifle with a bolt that cycles, pushing against an action spring will generally have a softer feeling recoil than say a bolt action gun.

Here is an example illustrating the math behind Primary Recoil:

Let's say that the gun is a .308/7.62, shooting a bullet that weighs 150 grains/9.7 grams at a velocity of 2820 ft/s, or 859 m/s. The gun weighs 9.9lbs/4.5 kgs.

Momentum (P) is mass (m) times velocity (v), or P=mv. Let's work out the momentum of the bullet (b).

Pb=mbvb or Pb=8.3kg m/s

The momentum of the bullet is 8.3kg m/s in the forward direction.

Now, since the net momentum of the system must be zero, the forward momentum of the bullet is balanced by the rearward momentum of the gun (g):

Pg=-Pb or mgvg=-mbvb

In our example above, with a weapon having a mass (mg) of 9.9lbs/4.5kg, the recoil speed of the rifle is:

vg=-Pb/mg or vg=-1.84 m/s

So, the primary recoil makes the gun move backwards into your shoulder at a velocity of 1.84 m/s.

If you add the propellant into the mix, the recoil speed is 2.6 m/s or 8.59 feet per second.

This happens BEFORE the bullet has left the muzzle.

A few videos that illustrate primary recoil, showing movement of the firearm before the bullet exits the muzzle:

http://www.youtube.com/watch?v=vvDDuQXYJzg
http://www.youtube.com/watch?v=nVEGfL_CXW4
http://www.youtube.com/watch?v=otpFNL3yem4

Blog post and video:
http://www.youtube.com/watch?v=MA52QznXmsQ
http://flat5.net/2008/11/straight-resistance-too/

http://www.youtube.com/watch?v=KfaqwxFpzGg

Some videos also show how secondary recoil works.

Now over to muzzle rise.

Muzzle rise occurs because the centerline of the barrel is above the center of contact between the shooter and the firearms' grips and stock. The recoil forces from the fired bullet and expanding gases exiting the muzzle act straight down the centerline of the barrel. If that line of force is above the center of the contact points, it creates a rotational force. The firearm will start to rotate, and the muzzle will rise upwards.

A diagram showing this:

http://img687.imageshack.us/img687/931/muzzlerise.png



Projectile and propellant gases act on barrel along barrel centerline A. Forces are resisted by shooter contact with gun at grips and stock B. Height difference between barrel centerline and average point of contact is height C. Forces A and B operating over moment arm / height C create torque or moment D, which rotates the firearm's muzzle up as illustrated at E.

----------------

That is the theory, and while the numbers and diagrams are good for mental masturbation, the most interesting is how does this affect me as a shooter.

Well, primary recoil effects, movement of the firearm before the bullet leaves the muzzle, reinforces the need for proper fundamentals when shooting a firearm. We know that the firearm moves before the bullet leaves the muzzle, so if our shooting position is poor, the movement of the fiream can increase, and affect POI.

Secondary recoil and muzzle rise theory reinforces the need for a good solid shooting position that allows for good recoil management, resulting in less dot/sight bounce and more rapid follow up shots. Muzzle rise effects also reinforce the need to grip as high up on a firearm as possible.

Secondary recoil and muzzle rise effects, and felt recoil are important factors when designing firearms and accessories; weapons that move less during the firing sequence are easier to control for the shooter.

Hope this makes sense.

Here is a very good recoil calculator, for those of you interested in numbers:

http://www.handloads.com/calc/recoil.asp

It's important to remember that the physics of recoil are the same regardless of operating mechanism. The main difference between operating mechanisms is how they cycle; or rather what makes them cycle.

In a short recoil mechanism, like on the Glock, the mechanism is cycled by recoil forces pushing back on the breech face, causing the slide and barrel to move back a short distance. The barrel then stops in the locking block, while the slide continues to recoil back.

So here you will have movement of both the operating mechanism, and the firearm itself.

http://www.youtube.com/watch?v=T4LT5GG7tC4&list=UULMnthnaGu0GWXIfAxrlA-w
http://www.youtube.com/watch?v=rZWW3GD5rEU&list=UULMnthnaGu0GWXIfAxrlA-w
http://www.youtube.com/watch?v=gossl577JHk&list=UULMnthnaGu0GWXIfAxrlA-w&index=30

In a gas operated gun, the recoil forces do not activate the operating mechanism, so they only push against the bolt face, causing rearwards movement of the gun. The mechanism is cycled using energy from the hot gases. That is why unlocking occurs after the bullet has exited the muzzle:

http://www.youtube.com/watch?v=OzeGPq23veU

The reciprocating parts do not alter the momentum of the gun/bullet-gas system. In a semi-automatic pistol, the reciprocating parts do alter the CG, this will effect the recoil characteristics of the weapon.

Then you will have the effects of secondary recoil, when the hot gases shoot out of the muzzle after the bullet.

The main culprit in terms of POI shift is that during primary recoil, there is also angular momentum, a rotation of the gun around its center of mass. This center of mass is below the center of the bore, also resulting in an upward angle change from the time the bullet is at rest and until it leaves the muzzle.

Arctic1
10-04-13, 02:16
Not as much as you would think.
Pat

Did you see the vid I posted?

http://www.youtube.com/watch?v=WOirbcsCQ1o

It does a good job of showing muzzle flip of several different pistols.

Omega Man
10-04-13, 04:11
I personally DO feel a noticeable difference in muzzle flip and my ability to shoot with more speed, between Sigs/HK's & Glock's/M&P's. Glock's & M&P's win for me.

Alaskapopo
10-04-13, 04:36
Did you see the vid I posted?

http://www.youtube.com/watch?v=WOirbcsCQ1o

It does a good job of showing muzzle flip of several different pistols.

That is a cool video and it showed the guns with the lower bore axis having the least muzzle flip.
Pat

montrala
10-04-13, 04:55
Did you see the vid I posted?

http://www.youtube.com/watch?v=WOirbcsCQ1o

It does a good job of showing muzzle flip of several different pistols.

I would not put much faith in this particular video. First of all, this is marketing material, not independent test. It is staged to proof predetermined point. Old Soviet saying was "if reality negates theory, too bad for reality".

They are also wrong on numbers, because it is distance from bore to closest pivot point, that is important. This pivot point is usually wrist. But then numbers would not be so impressive. Mere 10% improvement, not 100% or 200%. But we should also remember that most of modern combat/dynamic shooting techniques use body mechanics to move this pivot point even further, to elbows or even shoulders and use body mass inertia to absorb force. This makes "lenght of lever" (vocabulary shortages, sorry) differences even smaller.

On this video we see that shooter hands pivot first on wrist on most pistols then force transfers to forearm, but not on promoted pistol. Also initial forearm angle is not consistent with angle smallest.... yes, for shooting Striż. Some would say that this is that Stiż magic at work. For me, he just used more aggressive grip with locked elbows and wrist on promoted pistol, while grip on other pistols was more relaxed. But this is just my eyeballing.

BTW His grip with forearm at an angle (as used on most pistols) is preferred by some Open class shooter. They have brakes/comps to stabilize pistol, so no need to lock joints and holding pistol closer to the body makes swing motions easier and faster for target transitions.

Here is short video, made by my friend on recent shoot-off match we had. You can see how different pistols work for different level shooters trying to shoot fast. Nothing staged, everybody tries to do his best. No slo-mo unfortunately. Do not look only on muzzle flip, look also at what happens to wrist and forearm.

http://youtu.be/Sefr3-_V-wk

Urban_Redneck
10-04-13, 05:22
Did you see the vid I posted?

http://www.youtube.com/watch?v=WOirbcsCQ1o

It does a good job of showing muzzle flip of several different pistols.


I would not put much faith in this particular video. First of all, this is marketing material, not independent test. It is staged to proof predetermined point. Old Soviet saying was "if reality negates theory, too bad for reality"...


I agree with Montrala

The "test" results don't validate the premise, i.e. the Caracal F has "better" numbers than the G17, yet the Caracal fared worse. Therefore, either the premise is flawed or the testing is flawed.

Take your pick

Arctic1
10-04-13, 05:39
As I said in the first post, it is not definitive by any means, but does show that there is no real correlation between height of boreline over grip, and muzzle flip. If you look at the numbers, you would see this.

I also stated that it is biased, because it is a promotional video for the Strike One pistol.

I think you misunderstood the point of showing the vid. It was not to support the "high boreline guns have more muzzle flip" theory. It would be good if people actually read entire therads, before assuming a poster's position on a topic.

For further explanation on recoil, see my longer post above. It is the distance from the bore line to the center of the contact point(s) that is important, with regards to muzzle flip.

montrala
10-04-13, 06:00
I think you misunderstood the point of showing the vid. It was not to support the "high boreline guns have more muzzle flip" theory. It would be good if people actually read entire therads, before assuming a poster's position on a topic.

You also did not understand my point. This video is flawed from any point. It only supports idea that Striż (Strike One) is best thing since sliced bread.

BTW I hope to have opportunity to shoot one soon. Will report on that.

As to muzzle recoil angle, for me it could do full 360 if it just do it fast enough and barrel rests in desired point after cycle. I couldn't care less what pistol does in meantime, I'm interested in final outcome - I want it pointed back in right sport as fast as I'm able to utilize that. Faster does not matter, because I will be limiting factor anyway, slower is a problem. I do believe than bore axis height is only one for many factors that apply to overall motion dynamics in recoil and recovery and definitely not very important one (abominations excluded).

TiroFijo
10-04-13, 07:01
In a handgun with a normal service caliber, this "secundary recoil" is BS... the ejecta of high velocity gas (due to combustion of powder) is a very small fraction of total recoil.

I've seen plenty of high speed videos and it is clearly evident that by far most of the recoil in a pistol is when the slide hits the frame at the end of the rearward stroke. Up to that time the flip is minimal. There is no doubt that a higher bore would cause more flip, but as many said here the split times would probably depend a lot more on the shooter.

In a revolver it is different, there is no phase of "cushioned" recoil and the higher bore over the hand produces more muzzle flip, and from the very beggining. This is the reason why the zero with a revolver (specially a magnum) is shooter dependent, since how tight and high you grip the gun makes a noticeable difference. This is also the reason why the barrel is pointing DOWN when you align the sights on a level target at 25 yds.

Arctic1
10-04-13, 07:05
True, the video is hardly scientific in any way. To really measure muzzle flip or recoil characteristics you would need a completely unbiased shooter who has excellent and consistent technique, or a mechanical fixture designed for the purpose.

And to be honest, I can't make out much of a difference in the elbow angle of the shooter between the pistols. Besides, once you get into arm/elbow technique when shooting handguns, there really is no consensus on what is better. Some advocate arms fully locked, some advocate elbows rotated up, some advocate elbows slightly bent; amount differs.

The main point here is that there are many factors involved, and I think the shooter is a bigger factor in muzzle flip reduction, than bore line height. Training and technique trumps gadgets all day long, IMO.

I have mostly shot unmodified weapons; ie no comps, breaks, modified triggers, no special bolts or buffers or springs. For most of my career I have been able to shoot faster with better accuracy than many of my stronger and larger peers. I am 5'9" and weigh 165lbs.....I have to have good technique. :p

Arctic1
10-04-13, 07:29
In a handgun with a normal service caliber, this "secundary recoil" is BS... the ejecta of high velocity gas (due to combustion of powder) is a very small fraction of total recoil.

I've seen plenty of high speed videos and it is clearly evident that by far most of the recoil in a pistol is when the slide hits the frame at the end of the rearward stroke. Up to that time the flip is minimal. There is no doubt that a higher bore would cause more flip, but as many said here the split times would probably depend a lot more on the shooter.

In a revolver it is different, there is no phase of "cushioned" recoil and the higher bore over the hand produces more muzzle flip, and from the very beggining. This is the reason why the zero with a revolver (specially a magnum) is shooter dependent, since how tight and high you grip the gun makes a noticeable difference. This is also the reason why the barrel is pointing DOWN when you align the sights on a level target at 25 yds.

No, it is not BS. What I presented are the scientific factors involved with recoil. Primary and secondary recoil cannot be argued, it is what happens with every type of firearm using powder propelled projectiles passing through a barrel.

What do you think accelerates the slide backwards? Yup, primary and secondary recoil does. The majority of handguns are RECOIL operated.

The main difference between a rifle and the handgun is the mass of the reciprocating parts in relation to the rest of the gun; ie the frame in a handgun, and the number of contact points, in addition to the location of the contact points in relation to the bore line.

When a rifle bolt cycles, it really doesn't affect the CG that much. On a handgun, the shift in CG when the slide travels to the rear has a huge effect on recoil characteristics, because the formula/schematic I posted of muzzle flip in my previous post is not constant. This means that the effects of angular momentum are changed through the entire rearward travel distance of the slide.

The effect on muzzle flip and weapon movement when the slide stops at the end of it's rearward travel, has nothing to do with recoil (conservation of momentum - primary and secondary, and thrust force on the weapon when bullet uncorks - secondary), but it does affect felt recoil in the firearm and the angular momentum of the recoil forces imparted on the gun.

jondoe297
10-04-13, 08:04
Also 99.999999% of the pros are not using HK's or Sigs.
Pat

No offense, bro, but that's the last thing I'm concerned about when choosing a carry pistol, which is what the OP was inquiring about.
As for it being a "myth", I certainly don't believe that it is. I do, however fully believe that it's a minor factor (to the point of being irrelevant) when choosing a carry weapon. That's the angle that I approach any potential pistol from, as I'm not a competitive shooter and have little more than a passing interest in it.

TiroFijo
10-04-13, 08:11
Artic, simplified equations for recoil:

Mg*Vg = Mb*Vb + Mc*Vc

Where:

Mg,Vg = mass and velocity of the gun
Mb,Vb = mass and velocity of the bullet
Mc,Vc = mass and velocity of the powder charge

The average velocity of the powder gas column is about 1/2 the velocity of the bullet up to the bullet exit, then increases to about 1.5 the bullet velocity when it exits the bore. This is the "muzzle blast" effect and is very minor in typical calibers.

In a 9 mm with a 124 gr bullet @ 1200 fps, with a 6 gr. powder charge the powder mass accounts for only 6.8% of total recoil, and this fractions is even smaller when you consider only the muzzle blast effect.

So, even if it is there this muzzle blast effect is neggligible for all practical purposes.

C4IGrant
10-04-13, 08:28
Less distance less time. No offense but that is kind of like Duh. Also 99.999999% of the pros are not using HK's or Sigs.
Pat

You have to realize that most "pro's" are sponsored and are GIVEN their guns. This leaves HK out for sure.

When your are at the TOP echelon of the competition world, half of a second might mean the difference between winning and losing.

In this instance, having a gun that can shoot flat would be important. For EVERYONE ELSE, it matters not. What is more important is the reliability, ergonomics and accuracy of the gun.


C4

Caduceus
10-04-13, 08:30
It's an issue, but I think some people are more sensitive to it than others (ain't that the case with everything?)

For example, I shoot a Sig 229. I notice a drastic change in how the pistol bucks if I switch to a M&P or Glock and my natural point of aim ... or conversely, if I shoot one first then go back to the 229. Definitely bucks differently.

After 50-100 rounds though, it settles back down.

YVK
10-04-13, 08:54
Actually its the opposite. Since the gun has more leverage on the shooter and the gun moves more the slide actually returns slower.
Pat

Now you lost me. Let's break it on small pieces. Do you agree that slide has a higher leverage when it moves back into battery, as opposed to low axis guns?

decodeddiesel
10-04-13, 08:58
Artic, simplified equations for recoil:

Mg*Vg = Mb*Vb + Mc*Vc

Where:

Mg,Vg = mass and velocity of the gun
Mb,Vb = mass and velocity of the bullet
Mc,Vc = mass and velocity of the powder charge

The average velocity of the powder gas column is about 1/2 the velocity of the bullet up to the bullet exit, then increases to about 1.5 the bullet velocity when it exits the bore. This is the "muzzle blast" effect and is very minor in typical calibers.

In a 9 mm with a 124 gr bullet @ 1200 fps, with a 6 gr. powder charge the powder mass accounts for only 6.8% of total recoil, and this fractions is even smaller when you consider only the muzzle blast effect.

So, even if it is there this muzzle blast effect is neggligible for all practical purposes.

Your equation makes no sense as you are arriving at momentum. Recoil is a force, it's basic governing equation it F=ma.

Here's the bottom line from someone who gets paid a good deal of money to analyze things like this all day long (mechanical engineer).

The recoil of a semiautomatic pistol is a very dynamic situation with a lot of factors in play. An ME could literally spend a solid week, if not more analyzing this dynamic system and characterizing equations to govern it. It's not as simple as a few meaningless algebraic expressions slapped together. People go to school for years to develop the tools to analyze these things.

MistWolf
10-04-13, 09:19
In a handgun with a normal service caliber, this "secundary recoil" is BS... the ejecta of high velocity gas (due to combustion of powder) is a very small fraction of total recoil...

If this were true, muzzle brakes and compensators would not work


Artic, simplified equations for recoil:

Mg*Vg = Mb*Vb + Mc*Vc

Where:

Mg,Vg = mass and velocity of the gun
Mb,Vb = mass and velocity of the bullet
Mc,Vc = mass and velocity of the powder charge

The average velocity of the powder gas column is about 1/2 the velocity of the bullet up to the bullet exit

If this were true, the powder could not push the bullet, let alone accelerate it


then increases to about 1.5 the bullet velocity when it exits the bore. This is the "muzzle blast" effect and is very minor in typical calibers.

In a 9 mm with a 124 gr bullet @ 1200 fps, with a 6 gr. powder charge the powder mass accounts for only 6.8% of total recoil, and this fractions is even smaller when you consider only the muzzle blast effect.

So, even if it is there this muzzle blast effect is neggligible for all practical purposes.

What you are missing is the fact that the velocity of the ejecta from smokeless gunpowder has a constant velocity and is not dependent on muzzle velocity. If I recall, that constant is 5700 fps. Once the bullet uncorks the muzzle, the powder ejecta escapes at about 5700 fps. Years ago, I did some calculations using a formula to figure out the free recoil of different rifles. It turns out that the gunpowder ejecta contributes anywhere from one third to one half of the free recoil in most rifles (I did not do any calculations for handguns)

beschatten
10-04-13, 09:20
http://i.imgur.com/19kEQHG.jpg?1

The bore axis is not that relevant. The grip is the most important aspect to recoil management. The goal is the have more resistances for the gun to waste energy on to mitigate the rise.

If we could somehow superglue the gun to the web of our hand, the muzzle flip would be almost minimal because the muzzle rise has to fight against the super glue (resistance). Applying isometric tension creates a vector force of down, which also wastes more muzzle rise energy.

Edit: So what role does the bore axis play? It brings the web of your hand (the frictional coefficient) closer to where the slide traveling rearward is. Meaning it is closer to where you want the friction to be. In real-world applications, it really means nothing. It's the grip.

Failure2Stop
10-04-13, 09:37
I just want to go on record and state that while there is a physical and mathematical advantage to a lower bore axis, with contemporary design in addition to a near endless amount of variables (of which a major factor is shooter proficiency with the platform) it is pretty much irrelevant, and at this point is simply arguing minutia.

TiroFijo
10-04-13, 10:01
If this were true, muzzle brakes and compensators would not work

They do work, but work better iwith higher doses of powder... take into account that if the gas is deflected backwards the effect doubles.


If this were true, the powder could not push the bullet, let alone accelerate it

The powder velocity has little to do with bullet acceleration, it is the pressure...


What you are missing is the fact that the velocity of the ejecta from smokeless gunpowder has a constant velocity and is not dependent on muzzle velocity. If I recall, that constant is 5700 fps. Once the bullet uncorks the muzzle, the powder ejecta escapes at about 5700 fps. Years ago, I did some calculations using a formula to figure out the free recoil of different rifles. It turns out that the gunpowder ejecta contributes anywhere from one third to one half of the free recoil in most rifles (I did not do any calculations for handguns)

The powder the ejecte is NOT a constant, take a look at this, then perform your own calculations:

http://www.saami.org/PubResources/GunRecoilFormulae.pdf

TiroFijo
10-04-13, 10:10
Your equation makes no sense as you are arriving at momentum. Recoil is a force, it's basic governing equation it F=ma.

Here's the bottom line from someone who gets paid a good deal of money to analyze things like this all day long (mechanical engineer).

The recoil of a semiautomatic pistol is a very dynamic situation with a lot of factors in play. An ME could literally spend a solid week, if not more analyzing this dynamic system and characterizing equations to govern it. It's not as simple as a few meaningless algebraic expressions slapped together. People go to school for years to develop the tools to analyze these things.

You are right, but you missed the "simplified" part. It is better to find round basic numbers than to fool around with integrated F=m*a for the entire circle. From another engineer, if you perform these equations with a lot of detail, you'll arrive pretty much at the same numbers... This is a well known issue for more than a century. Read the link to .pdf by SAAMI.

Some engineers are victims of their own education and think that only using a computer and a very sophisticated model they'll get meaningful numbers. This is not the case.

Arctic1
10-04-13, 10:28
@TiroFijo:

I suggest that you look at slow motion/high speed footage of handguns being fired, and note the amount of angular momentum before the slide reaches it's end of travel. Try also to note how much movement there is during primary recoil, before the bullet exist, and after the bullet exits the bore before the slide stops it's rearward travel.

And I think what you are missing is that secondary recoil effects CAN be mitigated by technique. If that was not the case, and secondary recoil was BS, grip would not matter.

Compare a vid of a guy shooting one handed with a guy shooting with a strong two-handed grip.

And I agree that effects of a compensator is more prominent with bigger calibers, but the principle behind it remains the same; using "muzzle blast" to overcome the angular momentum that caused muzzle flip, by directing it upwards.

beschatten
10-04-13, 10:38
@TiroFijo:

I suggest that you look at slow motion/high speed footage of handguns being fired, and note the amount of angular momentum before the slide reaches it's end of travel. Try also to note how much movement there is during primary recoil, before the bullet exist, and after the bullet exits the bore before the slide stops it's rearward travel.

And I think what you are missing is that secondary recoil effects CAN be mitigated by technique. If that was not the case, and secondary recoil was BS, grip would not matter.

Compare a vid of a guy shooting one handed with a guy shooting with a strong two-handed grip.

And I agree that effects of a compensator is more prominent with bigger calibers, but the principle behind it remains the same; using "muzzle blast" to overcome the angular momentum that caused muzzle flip, by directing it upwards.

Is 'secondary recoil' when the slide reaches the maximum rearward travel and the energy from that slides momentum pushed into the hand, causing the muzzle rise? Not quite sure I follow with the differences between primary and secondary.

brickboy240
10-04-13, 10:47
I own two Glock 9mms (19 & 17) as well as two SIG 9mms (P225 & P228).

Although there is a difference in bore heights...sorry..I have not noticed enough recoil difference to make me want to ditch the SIGs and stick to only the Glocks.

There IS a difference...but not enough to seriously affect my shooting, make me get rid of the P225 or P228 or keep me from maybe getting a PPQ some day.

-brickboy240

Arctic1
10-04-13, 10:48
Secondary recoil is the momentum of the ejecta, hot expanding gases shooting out of the muzzle, causing a rocket-like effect.

The slide reaching the end of it's travel imparts a force one then gun/hand system, but is not part of the recoil itself although it affects felt recoil.

TiroFijo
10-04-13, 10:55
@TiroFijo:

I suggest that you look at slow motion/high speed footage of handguns being fired, and note the amount of angular momentum before the slide reaches it's end of travel. Try also to note how much movement there is during primary recoil, before the bullet exist, and after the bullet exits the bore before the slide stops it's rearward travel.

And I think what you are missing is that secondary recoil effects CAN be mitigated by technique. If that was not the case, and secondary recoil was BS, grip would not matter.

Compare a vid of a guy shooting one handed with a guy shooting with a strong two-handed grip.

And I agree that effects of a compensator is more prominent with bigger calibers, but the principle behind it remains the same; using "muzzle blast" to overcome the angular momentum that caused muzzle flip, by directing it upwards.

Artic1, like I said before, I've seen MANY high speed videos of pistols being shot, with lots of detail. To begin to understand what is happening you need at least 20000 frames per second, and more is better.

About 12 years ago, when I became interested in these tidbits I wrote to a lot of people becasue hi speed videos were not widerly available then and were treated like trade secrets. Perhaps you know the famous videos by Werner Mehl from Kurzzeit, I even nagged him to produce a close-up of a 1911 when the bullet uncorks to show how much really the slide had moved backwards (that matched my "senseless" calculations, BTW :D ). Same with Virgil Tripp that produced a very nice video on the same theme.

MistWolf
10-04-13, 11:04
The powder the ejecte is NOT a constant, take a look at this, then perform your own calculations:

http://www.saami.org/PubResources/GunRecoilFormulae.pdf

The formula I used looked just like the one for the SAAMI link. It was in one of my reloading manuals. However, they listed the ejecta velocity for modern smokeless gunpowder at (if I recall correctly) about 5700 fps. The SAAMI data is taken from 1929 when smokeless powders were significantly less vigorous than they are today.

Still, I should have noted the difference of ratio powder to bullet mass- with a typical 5.56, it's roughly 20 grs of powder to 60 grs of bullet whereas it's roughly 3 grs of powder to 115 grs of bullet

beschatten
10-04-13, 11:05
Secondary recoil is the momentum of the ejecta, hot expanding gases shooting out of the muzzle, causing a rocket-like effect.

The slide reaching the end of it's travel imparts a force one then gun/hand system, but is not part of the recoil itself although it affects felt recoil.

Understood. And yes I concur, the force of recoil can be mitigated so that the user/shooter receives a lesser amount of that force, whether primary or secondary.

TiroFijo
10-04-13, 11:09
The formula I used looked just like the one for the SAAMI link. It was in one of my reloading manuals. However, they listed the ejecta velocity for modern smokeless gunpowder at (if I recall correctly) about 5700 fps. The SAAMI data is taken from 1929 when smokeless powders were significantly less vigorous than they are today.
Still, I should have noted the difference of ratio powder to bullet mass- with a typical 5.56, it's roughly 20 grs of powder to 60 grs of bullet whereas it's roughly 3 grs of powder to 115 grs of bullet

We are talking about handguns in normal calibers here... ;)

misanthropist
10-04-13, 11:10
I just want to go on record and state that while there is a physical and mathematical advantage to a lower bore axis, with contemporary design in addition to a near endless amount of variables (of which a major factor is shooter proficiency with the platform) it is pretty much irrelevant, and at this point is simply arguing minutia.

IMO this is the bottom line. All else being equal, bore axis will make a small difference in the controllability of a given pistol.

Is all else equal? No. Bore axis is not a significant issue compared to any number of other factors and I don't worry about it any more.



Flawless, sub-moa fit and finish...all day long.

Arctic1
10-04-13, 11:11
Understood. And yes I concur, the force of recoil can be mitigated so that the user/shooter receives a lesser amount of that force, whether primary or secondary.

Primary recoil cannot be altered, as that is the momentum of the gun-bullet/gas system. This cannot be altered unless the mass of the gun changes or the mass of the bullet or charge changes.

beschatten
10-04-13, 11:15
Primary recoil cannot be altered, as that is the momentum of the gun-bullet/gas system. This cannot be altered unless the mass of the gun changes or the mass of the bullet or charge changes.

It cannot be mitigated for the gun, but what the user/shooter feels/receives can be. Force is energy, and energy can be wasted during a transfer (gun to shooter).

MistWolf
10-04-13, 13:38
We are talking about handguns in normal calibers here... ;)

So am I. Modern powders are much improved over what was available in 1929

trinydex
10-04-13, 13:52
"shooting it well" has to be defined. Will bore axis affect accuracy? It shouldn't. Will it affect your ability to get the gun back on target for follow-up shots? You betcha. Basic physics:

F=MV (force = mass * velocity). If there is a greater mass above the bore axis (as there is with a Sig compared to a Glock for example) then given an equal slide velocity, there will be a greater recoil force with the gun that has a higher bore axis.

There is some torque that plays into the equation as well based on the pivot point created by your hand but bottom line is a higher bore axis leads to more felt recoil and slower follow-up shots. It can be trained around, but it is a factor.

it is not simply the force. it is the force at a distance which creates torque.

the equation for torque is T = F*d where F is force and d is distance.

the larger the distance the higher the torque.

this is to say even if the height of the bore did not automatically increase the slide mass (if you made the slide out of titanium on the higher bore axis weapon) then you would still have the issue of the bore axis increasing the the torque value when compared to a sweapon with a lower bore axis.

GunBugBit
10-04-13, 14:09
The higher up the bore is the more leverage it has over your hand to flip the gun backwards.
Yes, it's physics, stated concisely above.

It makes a small difference, but it's small differences that win both competitions and real gunfights.

Failure2Stop
10-04-13, 14:12
Yes, it's physics, stated concisely above.

It makes a small difference, but it's small differences that win both competitions and real gunfights.

It's training, repetition, and dedication that wins competitions and gunfights on a far more frequent basis than bore axis.

GunBugBit
10-04-13, 14:13
It's training, repetition, and dedication that wins competitions and gunfights.
Training, repetition, and dedication yield the differences.

I'll add thinking.

YVK
10-04-13, 14:37
it is not simply the force. it is the force at a distance which creates torque.

the equation for torque is T = F*d where F is force and d is distance.

the larger the distance the higher the torque.

this is to say even if the height of the bore did not automatically increase the slide mass (if you made the slide out of titanium on the higher bore axis weapon) then you would still have the issue of the bore axis increasing the the torque value when compared to a sweapon with a lower bore axis.

Would you agree that torque value is increased also when slide is returning back into battery when compared to a weapon with a lower bore axis?

TiroFijo
10-04-13, 14:46
So am I. Modern powders are much improved over what was available in 1929

Do you realize most 9 mm loads of the type I posted are loaded with powders fairly similar to unique, that is 113 years old :D ?

In any case, the intention of my original post was just to show how little contribution has the muzzle blast effect in a normal service load, not to give a super accurate number. If you want ot increase the gas velocity a little go ahead and see how little things change.

For those nitpicking about accurate results, get someone to run a quickload recoil anaylisis, this is the real deal complete with all the curves of bullet velocity and pressure vs time, peak recoil, recoil at the moment of bullet exit, contribution of powder, etc.

trinydex
10-04-13, 14:48
Would you agree that torque value is increased also when slide is returning back into battery when compared to a weapon with a lower bore axis?

yes. action at a distance. except the return torque is coming from the force of the recoil spring.

WickedWillis
10-04-13, 14:52
My personal experiences; I shoot Sigs better than nearly every handgun I've ever fired. Great grouping, faster more accurate follow-ups, better at distance. Sig's bore axis is pretty high, but to me it doesn't seem to matter. I prefer Glocks (weight, capacity, parts) but I would stake my life on my 220. So I personally do not believe that bore axis matters that much.

beschatten
10-04-13, 15:03
it is not simply the force. it is the force at a distance which creates torque.

the equation for torque is T = F*d where F is force and d is distance.

the larger the distance the higher the torque.

this is to say even if the height of the bore did not automatically increase the slide mass (if you made the slide out of titanium on the higher bore axis weapon) then you would still have the issue of the bore axis increasing the the torque value when compared to a sweapon with a lower bore axis.

Wouldn't the distance be the length of the slide/frame travel? Not the distance between slide and bore axis?

MegademiC
10-04-13, 16:01
My 2 cents. It's more of an annoyance than a problem, I can't stand sigs or USPs because of this. It feels like the gun floats. I would say slide speed is equal with bore hight as far as considering a gun. A high, slow moving slide sucks IMO. Others may love it.

As for effect, I'd be willing to bet it comes down to training and would never matter in a fight if you trained how you should. That said I haven't timed myself... Yet.

MegademiC
10-04-13, 16:03
Wouldn't the distance be the length of the slide/frame travel? Not the distance between slide and bore axis?

Impulse is what I think your describing. Force can be constant but if your lengthening the stick its on( think holding a stick) the torque increases.

trinydex
10-04-13, 16:25
Impulse is what I think your describing. Force can be constant but if your lengthening the stick its on( think holding a stick) the torque increases.

impulse is described as the integral of the force over time with respect to time. so he would be incorrectly thinking impulse if that was indeed what he was thinking.

trinydex
10-04-13, 16:35
Impulse is what I think your describing. Force can be constant but if your lengthening the stick its on( think holding a stick) the torque increases.

the force is moving along the axis that the slide and barrel and etc reside along.

however that force (longitudinal) is acting a certain distance away from a fulcrum (namely your wrist/hand/backstrp of the gun/etc), torsionally. that distances turns the force into a torque on your wrist/hand.

Frailer
10-04-13, 18:30
Oops. Never mind. The physics was already thoroughly covered.

MistWolf
10-04-13, 18:35
...In any case, the intention of my original post was just to show how little contribution has the muzzle blast effect in a normal service load...

Yes, I realize that, and the recoil from the powder ejecta is less in a pistol round than a rifle. That's why I said

...Still, I should have noted the difference of ratio powder to bullet mass- with a typical 5.56, it's roughly 20 grs of powder to 60 grs of bullet whereas it's roughly 3 grs of powder to 115 grs of bullet
I should have tacked "with a typical 9mm" on the end. Or something

foxtrotx1
10-04-13, 20:51
Seems like some members would rather sail the Glock fanboat all the way to the moon rather than realize we all have different tastes so no one pistol is superior in terms of speed.

chilic82
10-05-13, 08:46
Seems like some members would rather sail the Glock fanboat all the way to the moon rather than realize we all have different tastes so no one pistol is superior in terms of speed.

Agreed. I have been worn out by the Glock fanboat for owning a XDm. They claim the gun isn't worth buying because the bore axis is higher than a glock, but then I catch them blabbering about how much they love Sigs and HK's. I don't get it.:confused:

MegademiC
10-05-13, 15:16
the force is moving along the axis that the slide and barrel and etc reside along.

however that force (longitudinal) is acting a certain distance away from a fulcrum (namely your wrist/hand/backstrp of the gun/etc), torsionally. that distances turns the force into a torque on your wrist/hand.

Yea, I misread it... Fine print on a phone and all.

T2C
10-05-13, 16:14
Seems like some members would rather sail the Glock fanboat all the way to the moon rather than realize we all have different tastes so no one pistol is superior in terms of speed.

I am a huge fan of Glock. I never bring it up unless asked when I am teaching a pistol class. Some people shoot other makes of pistols much better than Glocks and all I am looking for is marked improvement at the end of a course. I have seen people excel with HK, S&W, Glocks, etc., so I say pick what works best for you.

In my opinion the distance of the bore axis over fulcrum point is a general rule of thumb when selecting a handgun. I believe that reciprocating mass, spring rate and slide speed also play a role in felt recoil. You just don't know until you actually fire the pistol.

Even if you have an increase in felt recoil, pistol ergonomics may help you get back on target faster.

Choose what works best for you and shoot the daylights out of it!

HKGuns
10-05-13, 21:38
I shoot all sorts of different pistols and shoot most of them pretty well. Some better than others, but that is primarily because I shoot them more often.

High Bore Axis = The primary excuse used by poor or inexperienced shooters to explain their lack of practice and/or adaptability. Or, the excuse used to denigrate an otherwise perfectly good pistol. (It's reliable, accurate, comfortable....Oh, but it has a high bore axis so it isn't worth $hite.)

There are far too many other variables involved, including the grip of the gun and the grip of the shooter. I don't buy pistols based on their high/low bore axis. -That would be silly.

Surf
10-06-13, 14:19
Too long of a thread to read through, so I am sure some of this has been covered but here is my take on it.

Now if we are talking slow fire accuracy, most pistol platforms can be dealt with effectively with good mechanics / fundamentals. With rapid fire strings several factors add up to make significant differences. Yes, bore axis height is a factor, but it is only but one piece of the puzzle and not necessarily the most important factor either.

So all things being equal, bore axis height is a factor. So if I am asked if bore axis height makes is an advantage, my answer is "yes, butt....." However most things are not equal from pistol to pistol and factors such as length, weight, balance, slide mass, recoil springs, grip angles, beavertails, caliber, load, shooter, etc, all play a role in how a pistol performs.

So if I look at a quick comparison of say a 9mm Sig P226 Classic vs a Glock 17 there is a small but definite performance difference, going to the Glock. But again that is not necessarily due to the bore axis, but moreso a combination of factors.

Now if I look at say a 9mm Sig P226 Classic vs a 9mm Sig P226 Elite, we are getting a good comparison of how a beavertail adds leverage and allows me to shoot faster strings of fire with smaller group sizes. Similar in theory to how a beavertail on a 1911 platform aids in recovery. Is it the only reason? No it is not the sole factor but a large part of the overall puzzle.

Now if I compare a box stock G17 vs one of my custom G17's with undercuts, grip modifications, I do show a difference in my performance. Very slight, but at where I am with my shooting, it is noticeable and I do have a preference. So is it that I am getting my hand placement higher on to the bore axis, or is it changing my leverage on the gun? Yes. Both are correct in my mind.

So does bore axis height matter? Yes it does. How much does it matter? Depends on a lot of variables. Is it THE deciding factor for recovery? Depends again, but mostly it is just one of the things to look at. In some designs it may play a bigger role than in others.

Alaskapopo
10-06-13, 14:29
I shoot all sorts of different pistols and shoot most of them pretty well. Some better than others, but that is primarily because I shoot them more often.

High Bore Axis = The primary excuse used by poor or inexperienced shooters to explain their lack of practice and/or adaptability. Or, the excuse used to denigrate an otherwise perfectly good pistol. (It's reliable, accurate, comfortable....Oh, but it has a high bore axis so it isn't worth $hite.)

There are far too many other variables involved, including the grip of the gun and the grip of the shooter. I don't buy pistols based on their high/low bore axis. -That would be silly.

Lol. If you feel that shooters like myself are that poor and inexperienced come on out to any USPSA, IDPA or three gun match of your choosing and go ahead and give us a lesson with one of those HK's of yours. I have a feeling you would go home crying.

The reality is your choosing to trivialize something because your particular pistol choice has a weakness in that area.

Mjolnir
10-06-13, 14:38
To bring another point to the table--
Has anyone shot the new Chiappa Rhino revolver? I shot one at SHOT this past year in .357 Mag. The recoil is "different.' Although it may not flip the muzzle as much, it puts more of the force in the palm. I don't know if it was just the ergonomics of the grip, but it felt as "bad" as shooting as M&P340 Scandium frame 357 Mag. Like a Hammer smacking your hand on concrete.

The steyr M9 is one of the best examples of the low bore axis. It does prevent the muzzle flip more so than a Sig, but it isn't enough of a difference to go for it over a Glock or M&P due to availability to find parts and holsters and mags, etc.

Good point - especially the Rhino.

I'd much prefer muzzle flip to POUNDING the palm of my dominant hand.

There is a limit to both and that will vary with the individual. Some will like the Sig P226 while others will prefer the Steyr or Glock. Each is, of course, correct for him/her self.

What I do is up the caliber and try it again. I know I prefer the flip even though it slows me SOME but it's "no big deal" as I seem to "find time" while its returning to its initial position to reproduce the fundamentals once the sights are back on target.

Slower? Marginally. But I slow down (my flaw is that I like to go FAST) so it's noticeable but not crippling by any measure.

Oh, the proper term is "Moment" which is Force x Distance (perpendicular to the line of force). And what we perceive is PERCEIVED; not necessarily what is. Other things confound it such as ergonomics.

The total energy of the pistols are the same from the cartridge (assuming same barrel length and same cartridge). Mass of barrel, mass of slide and bore axis plus grip angle and ergos will round the equation.


-------------------------------------
"One cannot awaken a man who pretends to be asleep."

Failure2Stop
10-06-13, 15:22
Lol. If you feel that shooters like myself are that poor and inexperienced come on out to any USPSA, IDPA or three gun match of your choosing and go ahead and give us a lesson with one of those HK's of yours. I have a feeling you would go home crying.

The reality is your choosing to trivialize something because your particular pistol choice has a weakness in that area.

Remember that 1911s have similar bore height to Sigs and HKs.

Typos brought to you via Tapatalk and autocorrect. now Free ('http://tapatalk.com/m?id=10')

Alaskapopo
10-06-13, 15:27
Remember that 1911s have similar bore height to Sigs and HKs.

Typos brought to you via Tapatalk and autocorrect. now Free ('http://tapatalk.com/m?id=10')
Going to have to respectfully disagree with you there. 1911's have a bore axis closer to a Glocks than a HK's or a Sigs.
Pat

montrala
10-06-13, 15:39
Some interesting aspects of this matter were discussed before in this (short - 2 pages) thread: http://m4carbine.net/showthread.php?t=102985

Failure2Stop
10-06-13, 15:40
Going to have to respectfully disagree with you there. 1911's have a bore axis closer to a Glocks than a HK's or a Sigs.
Pat

From another forum:



So, I got curious about bore axis heights, and started using photos from the internet to measure bore axis heights on various guns. I first scaled all the photos using their barrel lengths, and then measured the distance from the bore axis of each gun to what seemed like the highest point of control for the firing hand. On autoloading pistols this highest point was taken to be where the tangential slope of the tang exceeded 45 degrees (ie, when the tang "flattens out" to the horizontal). On revolvers the highest point was taken to be that of the highest point of contact attainable along the backstrap. Now, I'm completely willing to conceed that this might not be "the" best way to estimate the height of the bore axis with regard to the shooter's hand (there might not even be a "best" way). But it is at least a consistent way to measure.

Here are some bore axis height measurements (in inches):

Sig 226 1.44"
M1911 (GI spec) 1.33"
HK P30 1.25"
1911 (beavertail safety) 1.2"
S&W M&P40 1.08"
SA XDm 1.05"
Walther PPs 1.00"
Glock 19 0.89"
Steyr M9 0.85
S&W N-frame (highest possible grip I can get w/ magnas) 0.85" (!!)
Ruger LCR 0.80"


Also, since the point of leverage terminates at the wrist (as the gun is locked in the firing hand), grip angles more perpendicular with the bore (ala 1911) result in greater leverage being pushed to the wrist.

Tzed250
10-06-13, 15:59
From another forum:



Also, since the point of leverage terminates at the wrist (as the gun is locked in the firing hand), grip angles more perpendicular with the bore (ala 1911) result in greater leverage being pushed to the wrist.

Interesting. I think the quote points to the reason that the Steyr M-A1 series are often described as having soft recoil.

Redhat
10-06-13, 16:49
Also, since the point of leverage terminates at the wrist (as the gun is locked in the firing hand), grip angles more perpendicular with the bore (ala 1911) result in greater leverage being pushed to the wrist.

But when the grip angle is increased, does it not affect other factors such as trigger manipulation? I have a suspicion that with Glocks, the angle of the grip and trigger together might create some challenges.

EDIT for additional question*

Since it appears I have some more time, at what grip angle do you guys think the wrist is stronger, Glock or 1911?

Failure2Stop
10-06-13, 16:56
But when the grip angle is increased, does it not affect other factors such as trigger manipulation? I have a suspicion that with Glocks, the angle of the grip and trigger together might create some challenges.

I agree. However, I don't think that the angle of the Glock grip in regard to trigger control is a significant factor. It does, however, integrate with a high support hand grip with good rotation of the support wrist.
I think that there are far too many variables between different pistols to get too wrapped around any single aspect.
If we were discussing identical pistols, with the only difference being bore axis, I would most likely opt for/prefer the one with the lower axis.

Alaskapopo
10-06-13, 17:01
From another forum:



Also, since the point of leverage terminates at the wrist (as the gun is locked in the firing hand), grip angles more perpendicular with the bore (ala 1911) result in greater leverage being pushed to the wrist.

That is interesting because the XD seems to have a high bore axis while the 1911 a much lower one. I would like to see where that poster got the numbers.
Pat

Failure2Stop
10-06-13, 17:52
Since it appears I have some more time, at what grip angle do you guys think the wrist is stronger, Glock or 1911?

I have seen compelling arguments for both.
Seems to me that from a pure physics standpoint, the Glock angle would bring the fulcrum of the wrist closer to the bore line, and thus result in less mechanical advantage of the pistol against the wrist.

However, I have heard that from the anatomical approach, the arm/grip is stronger as the grip angle is increased toward 90 degrees.

The anatomical standpoint of the grip seems to be a bit off to me, as the grip of the firing hand doesn't really seem to fail to keep the gun planted in the hand once sufficient grip strength is learned.

So, in short; I don't know.
I shoot 1911s, G21s, HK45s, and M&P45s all at about the same level once I have some time on the gun.


That is interesting because the XD seems to have a high bore axis while the 1911 a much lower one. I would like to see where that poster got the numbers.
Pat

I think it comes in where one measures the axis from.
I think that the most consistent/relevant measurement is from where the web of the firing hand would contact the grip perpendicular to the bore, to the center-line of the bore.

Really though, that measurement in actual use should be between the center-line of the bore and the center of the wrist, as the bore line is where the force acting against the lever of the pistol's grip is applied and the fulcrum is the wrist of the firing hand.

StrikerFired
10-06-13, 18:11
It's still going to be about shooter preference and training time on your platform. I know I can shoot my Glocks all day long. But this year as I logged more rounds on my Sig 220 I became just as accurate with it, and I as I get more familiar with the DAK trigger I will get just as fast splits.

I used to use the Bore Axis argument myself, but it seems like just a minor adjustment and not a primary consideration for a duty gun.

C4IGrant
10-06-13, 18:27
Lol. If you feel that shooters like myself are that poor and inexperienced come on out to any USPSA, IDPA or three gun match of your choosing and go ahead and give us a lesson with one of those HK's of yours. I have a feeling you would go home crying.

The reality is your choosing to trivialize something because your particular pistol choice has a weakness in that area.

I would be careful with such statements. There are people on this forum that will BURN YOU DOWN with a hi-point pistol.

It is always the Indian. ;)


C4

Alaskapopo
10-06-13, 18:38
I would be careful with such statements. There are people on this forum that will BURN YOU DOWN with a hi-point pistol.

It is always the Indian. ;)


C4

I doubt HKguns is one of them. But hey he can meet me at the Ft. Benning match this year and show me what he's got. At the last major match I was at I finished in the top 20% of my division.
HKguns was making the statement than anyone who talks about a low bore axis mattering is a poor inexperienced shooter which is clearly not the case.

C4IGrant
10-06-13, 18:41
I doubt HKguns is one of them. But hey he can meet me at the Ft. Benning match this year and show me what he's got. At the last major match I was at I finished in the top 20% of my division.
Pat


LOL, how would you know? Its not like he puts his USPSA ranking in his Sig Line.



C4

Alaskapopo
10-06-13, 18:44
LOL, how would you know? Its not like he puts his USPSA ranking in his Sig Line.



C4

You can tell a lot about a person by the ignorant way they speak. Calling anyone who disagrees with you an inexperienced poor shooter is ignorant. Good shooters know to take every advantage they can and they look for any edge they can get as well.
Pat

Alaskapopo
10-06-13, 18:50
You have to realize that most "pro's" are sponsored and are GIVEN their guns. This leaves HK out for sure.

When your are at the TOP echelon of the competition world, half of a second might mean the difference between winning and losing.

In this instance, having a gun that can shoot flat would be important. For EVERYONE ELSE, it matters not. What is more important is the reliability, ergonomics and accuracy of the gun.


C4
When is the time you attended a match Grant. Your making statements that are not true. I have a friend that is a Rudy Projects sponsored shooter and he is not given a gun. Sure guys who are sponsored by gun companies generally are but they don't make up the bulk of sponsored shooters. There is also different levels of sponsorship as well. HK is left out because frankly they suck in a competition setting. They don't make a competitive pistol and that is why you don't see many people using them. In real life hitting the target quickly does matter just like in competition. Having a gun that shoots flat helps with that. Slow and inaccurate does not win gun fights or competitions.

C4IGrant
10-06-13, 18:50
You can tell a lot about a person by the ignorant way they speak. Calling anyone who disagrees with you an inexperienced poor shooter is ignorant. Good shooters know to take every advantage they can and they look for any edge they can get as well.
Pat

Yes, you can Pat.


C4

C4IGrant
10-06-13, 18:54
When is the time you attended a match Grant. Your making statements that are not true. I have a friend that is a Rudy Projects sponsored shooter and he is not given a gun. Sure guys who are sponsored by gun companies generally are but they don't make up the bulk of sponsored shooters. There is also different levels of sponsorship as well. HK is left out because frankly they suck in a competition setting. They don't make a competitive pistol and that is why you don't see many people using them.

LOL. Pat, you have no idea.



C4

STAFF
10-06-13, 19:04
Thread has been cleaned up. Stick to a technical discussion on guns. Stay away from bickering and instigating fights.

Tzed250
10-06-13, 19:36
For me, I believe as much or more recoil control comes from my support side as does from my strong side. The top of the backstrap against the web of my hand is the upper pivot. The tension of my support hand on the bottom of the front strap is the torque control. I think this allows me a little better trigger control. That being said, I'm still a novice with a combat handgun.

Striker
10-06-13, 19:43
HK is left out because frankly they suck in a competition setting. They don't make a competitive pistol and that is why you don't see many people using them. In real life hitting the target quickly does matter just like in competition. Having a gun that shoots flat helps with that. Slow and inaccurate does not win gun fights or competitions.

But in "real life" DEVGRU seems to do just fine with the Sig P226/228 and HK45CT. And IIRC, didn't Jason Falla say that the SASR used the USP 9? All of which have what many consider to be a less than optimum trigger system (TDA) and high bore axis. This indicates that in real life these are not huge determining factors, rather the operator/shooter/indian really is.

Failure2Stop
10-06-13, 20:02
For me, I believe as much or more recoil control comes from my support side as does from my strong side. The top of the backstrap against the web of my hand is the upper pivot. The tension of my support hand on the bottom of the front strap is the torque control. I think this allows me a little better trigger control. That being said, I'm still a novice with a combat handgun.

If the web of the firing hand is the pivot point then you would be losing the grip of your lower fingers.

Recoil bends the wrist of both hands.
Take a look at high speed video of a pistol firing in the hand.
For this discussion the support hand has to be taken out of the equation, and due to the variability of hand sizes, even the firing hand has to be removed, leaving only the radius of the backstrap as a consistent reference point.

Typos brought to you via Tapatalk and autocorrect. now Free ('http://tapatalk.com/m?id=10')

Suwannee Tim
10-06-13, 20:07
Why do I always miss the good arguments?

FChen17213
10-06-13, 20:24
Low bore axis is just one piece of the puzzle. There are many many pieces of the equation when it comes to recoil control as previous people have mentioned. I think there are many valid points made here. There are people who shoot well with Glocks, XDs, M&Ps, 1911s, Sigs, etc etc. Each to his own.

I will say this though. I wish more people shot USPSA and IDPA constantly on here. Why? Because at least it's a yardstick that we can measure. Just like if everyone on here posted their 700 AG score honestly and Hack score honestly, we can get a measure.

I like competition classifications and such because it's a measuring stick, at least in terms of pure shooting. No, not gun fighting or survival, but just pure shooting. It's still a standard though. Don't know how many real USPSA GMs or Distinguished IDPA Masters we have on M4carbine but I am fortunate enough to be able to go to matches weekly and monthly where I can watch such people shoot. They are truly amazing. Alaskapopo, since you shoot USPSA regularly too, I'm sure you know what I'm talking about, watching the Super Squad full of Masters and GMs. Truly amazing.

C4IGrant
10-06-13, 20:25
But in "real life" DEVGRU seems to do just fine with the Sig P226/228 and HK45CT. And IIRC, didn't Jason Falla say that the SASR used the USP 9? All of which have what many consider to be a less than optimum trigger system (TDA) and high bore axis. This indicates that in real life these are not huge determining factors, rather the operator/shooter/indian really is.

Correct. Someone once said to me that they never looked at their "split times" when they were killing bad guys. This always made me laugh.

Guns with high bore access should REALLY only concern those folks that are at the TOP of the competition world (were tenths of seconds matter). For EVERYONE else (including "B" class competition shooters), it is 100% irrelevant. Not choosing a gun because it has a high bore access for an LE/CCW/Military/HD firearm is simply moronic.

If anyone watched the Delta show on the Military Channel (http://military.discovery.com/tv-shows/delta-force-tier-1/delta-force-tier-1-video/delta-force-tryouts.htm) Kyle Lamb had an interesting comment. He stated that Delta shooters were not master class competition shooters. They WERE however combat effective and got the job done. This was interesting to say the least.



C4

Tzed250
10-06-13, 21:06
If the web of the firing hand is the pivot point then you would be losing the grip of your lower fingers.

Recoil bends the wrist of both hands.
Take a look at high speed video of a pistol firing in the hand.
For this discussion the support hand has to be taken out of the equation, and due to the variability of hand sizes, even the firing hand has to be removed, leaving only the radius of the backstrap as a consistent reference point.

Typos brought to you via Tapatalk and autocorrect. now Free ('http://tapatalk.com/m?id=10')

I see your point. I guess pivot is the wrong word. The force of recoil is concentrated in the backstrap radius. If you were to fire a conventional pistol without your fingers wrapped around the grip would it not try to roll up over the top of your wrist?

As has been pointed out I believe that it is many factors that go into a controllable platform. A low bore axis is one of them. The ability to use your hands in recoil control is another, so a low bore axis needs to come with a grip that is effective.

As an absolute the low bore axis is better, but it has to mesh with the rest of the pistol to be any good, IMHO.

YVK
10-06-13, 21:08
I will say this though. I wish more people shot USPSA and IDPA constantly on here. Why? Because at least it's a yardstick that we can measure. Just like if everyone on here posted their 700 AG score honestly and Hack score honestly, we can get a measure.


How is it relevant to this kind of discussion? I could understand if we were talking about technical advice on shooting techniques etc, but for this type of discussion? I am not comparing myself to anybody, nor do I care who uses what, competition masters or alphabetized units.
I am my own control. I carried a low axis, short trigger travel Glock 19 for two years, shot it for 15K rounds and recorded my data. I carried a high axis, long trigger travel P30 for two years, shot it for 18K rounds and recorded my data. I could be C level and somebody could be M, but unless he took as much effort and data collection to provide his opinion, I dont really care.

HKGuns
10-06-13, 23:29
Hey, cold climate LEO, I gather from the quoted material you have, once again, taken issue with my post in this thread.

As my mother once told me, if the shoe fits, wear it, otherwise just let it go. You certainly seem befuddled by something that certainly would not apply to such an experienced, advanced and accomplished shooter as you put yourself forward as being.

I certainly hope you maintain your composure on the job better than you do on this site. You are entitled to your opinion, just as I am entitled to mine. I refuse to argue, even though you appear ready to argue about a lot of things that really shouldn't be "that" important.

Edit: Oh, I now see you have challenged me to an IDPA match! How fun! Sort of like a duel in cyberspace!

What do you suppose the bore axis is on this? You can shoot your low power factor 9mm and I will roll with this one, sound good?

http://hkguns.zenfolio.com/img/s8/v78/p1423643648-5.jpg

Arctic1
10-07-13, 03:15
Artic1, like I said before, I've seen MANY high speed videos of pistols being shot, with lots of detail. To begin to understand what is happening you need at least 20000 frames per second, and more is better.

About 12 years ago, when I became interested in these tidbits I wrote to a lot of people becasue hi speed videos were not widerly available then and were treated like trade secrets. Perhaps you know the famous videos by Werner Mehl from Kurzzeit, I even nagged him to produce a close-up of a 1911 when the bullet uncorks to show how much really the slide had moved backwards (that matched my "senseless" calculations, BTW :D ). Same with Virgil Tripp that produced a very nice video on the same theme.

Handgun recoil truly is a complex issue.

However, I wanted to make a new point, to expound on what I stated in my long post explaining recoil. This refers to secondary recoil in particular.

You said that secondary is BS in a semi-auto handgun. It might affect muzzle flip less than the force imparted to hand when the slide reaches the end of it's rearward travel, but it is still a factor. The difference is that you have a recoil spring that slows the acceleration of the slide, thereby lessening the effect. That is an example of how weapon design reduces secondary recoil effects; you still cannot remove the phenomenon.

To illustrate, take a look at this video:

http://www.youtube.com/watch?v=B-jzkDviIwo

Same caliber used, although .45 and not 9mm. As you can see, the revolver also rockets back when discharged, and it does not have any reciprocating mass. This is secondary recoil.

Arctic1
10-07-13, 03:22
Your equation makes no sense as you are arriving at momentum. Recoil is a force, it's basic governing equation it F=ma.

I am curious, as I have never seen recoil adressed as a force, only momentum. Could expound on why you would use the term force and not momentum? Shoot me a PM if you like.

TiroFijo
10-07-13, 06:02
Handgun recoil truly is a complex issue.

However, I wanted to make a new point, to expound on what I stated in my long post explaining recoil. This refers to secondary recoil in particular.

You said that secondary is BS in a semi-auto handgun. It might affect muzzle flip less than the force imparted to hand when the slide reaches the end of it's rearward travel, but it is still a factor. The difference is that you have a recoil spring that slows the acceleration of the slide, thereby lessening the effect. That is an example of how weapon design reduces secondary recoil effects; you still cannot remove the phenomenon.

To illustrate, take a look at this video:

http://www.youtube.com/watch?v=B-jzkDviIwo

Same caliber used, although .45 and not 9mm. As you can see, the revolver also rockets back when discharged, and it does not have any reciprocating mass. This is secondary recoil.

Artic1, of course there is a "jet effect" in recoil, my comment on "BS" was meant towards the very little importance of this effect in handgun service calibers...

Now, if you can see anything on a 1000 fps video you are a MUCH better man than me :) To me it is like trying to measure milimeters with a ruler marked in meters.

Like I said before, at least 20000 frames per second for a decent analysis, and more is MUCH better. Just barrel time for a 45 ACP in a 1911 is about 1 milisecond.

jondoe297
10-07-13, 07:53
Not choosing a gun because it has a high bore access for an LE/CCW/Military/HD firearm is simply moronic.



This x eleventy billion.

Psalms144.1
10-07-13, 08:52
Put me in the category where grip angle matters more than average. Due to a number of injuries (compound fracture left wrist with plate/screws to stabilize, both 5th fingers shattered and partially "frozen") the hard-rotated support hand simply doesn't work out for me. So, being "handicapped" with having to use the old fashioned two handed grip SLIGHTLY modified, I find that the Glock grip angle is a lot less forgiving for me bringing my sights on target quickly from the holster. The HK/1911/M&P grip angle "points" much more naturally for me, despite DECADES of training and hundreds of thousands of rounds through various Glocks.

Back to point, has anyone done any side-by-side comparisons of muzzle flip (or lack thereof) between GFA/Glock Beavertail equipped Glocks and "standard" Glocks? I'd be very interested in the results of that shoot-off, especially in some of the harder recoiling Glocks (like the G23 or G27).

Regards,

Kevin

YVK
10-07-13, 09:27
Back to point, has anyone done any side-by-side comparisons of muzzle flip (or lack thereof) between GFA/Glock Beavertail equipped Glocks and "standard" Glocks? I'd be very interested in the results of that shoot-off, especially in some of the harder recoiling Glocks (like the G23 or G27).

Regards,

Kevin

Excellent question. GFA is the only thing that I can't think of that allows to test different bore axis in otherwise identical guns. I know a number of people who tested it with 9 mm Glocks, and I don't know a single person who reported different split times and based their decision on those times.

sadmin
10-07-13, 10:10
I think over all its inconsequential in the scheme of things as mentioned early in the thread. Not to jock on this dude...but...to reiterate there are other factors that can be prioritized higher than bore axis height.


http://i7.photobucket.com/albums/y283/r3h4b/f1fdf616-2c21-442a-a4c6-312ec4dc435c_zps9260dcb0.jpg (http://s7.photobucket.com/user/r3h4b/media/f1fdf616-2c21-442a-a4c6-312ec4dc435c_zps9260dcb0.jpg.html)

Failure2Stop
10-07-13, 10:29
Oh, almost forgot, if you really want to put in perspective how minute the bore axis measurement is:

A modern 2-handed grip executed properly will see recoil transferred to the elbows, making the measurements involved in the height differential truly minuscule.

Video
http://www.youtube.com/watch?v=_O-Wedt3N4U

rvb
10-07-13, 10:30
Not sure I want to jump into this fray! :eek:

Even Brian Enos states we shouldn't care how high the sights lift, just that they return to the same spot... and that's what's ultimately important for high-speed shooting. We need to keep that in mind. That's a function of proper timing, grip, and index. That's what leads to fast/accurate splits.

However, I think lower bore heights do help, but not for the reason most people assume. I think factors like low bore-height, lightened slides, tuned ammo (typically heavier bullets w/ fast powders) help since the reduction in how high and how fast the sights lift aids my shot calling and sight tracking (not my splits!).

The more "flat" I can make my guns shoot, the easier and more accurate my shot calling and sight tracking becomes. The more violent the action is, more is going on visually.

The differences are very minor, but can be noticable if shooting an El prez or bill drill or a steel challenge stage. It would, however, be one of my last considerations in choosing a pistol (either for games or more "practical" uses). If person A beats person B in a shooting contest, I don't think we could say victory was won or lost because of bore height.

Just my 2cents.

-rvb [USPSA Master]

rvb
10-07-13, 10:35
I think over all its inconsequential in the scheme of things as mentioned early in the thread. Not to jock on this dude...but...to reiterate there are other factors that can be prioritized higher than bore axis height.



If we're bringing bob v into it, we might as well get the scoop right from the horses mouth...

http://www.vogeldynamics.com/gear/


Since the beginning of 2006 I have shot Glock pistols exclusively in competition. Prior to this I had shot 1911 style pistols (STI) for three solid years. My number one reason for preferring the Glock is the grip I am able to get on the pistol. Because of the grip angle, ergonomics and low bore axis of the pistol I can get a much higher and more secure grip with both hands. This in effect translates into a shooting platform that is more effective in controlling recoil.

-rvb

glocktogo
10-07-13, 11:26
Correct. Someone once said to me that they never looked at their "split times" when they were killing bad guys. This always made me laugh.

Guns with high bore access should REALLY only concern those folks that are at the TOP of the competition world (were tenths of seconds matter). For EVERYONE else (including "B" class competition shooters), it is 100% irrelevant. Not choosing a gun because it has a high bore access for an LE/CCW/Military/HD firearm is simply moronic.

If anyone watched the Delta show on the Military Channel (http://military.discovery.com/tv-shows/delta-force-tier-1/delta-force-tier-1-video/delta-force-tryouts.htm) Kyle Lamb had an interesting comment. He stated that Delta shooters were not master class competition shooters. They WERE however combat effective and got the job done. This was interesting to say the least.

C4

I dropped off this thread when it went full nerd. Now that it's swung back a little from theoretical physics and more towards actual shooting, I'd make the counterpoint that it's merely a function of training time. Delta has to make training judgements based on practical concerns. However, were they all GM's or Masters (in both rifle and pistol), in what way would that effect their combat efficiency? What I've always stated is that firearms proficiency instilled through the rigors of competition has nothing to do with tactics. It does however free mental capacity to focus on tactics, as the shooting portion of the equation will be subconsciously ingrained and take care of itself. :)


Not sure I want to jump into this fray! :eek:

Even Brian Enos states we shouldn't care how high the sights lift, just that they return to the same spot... and that's what's ultimately important for high-speed shooting. We need to keep that in mind. That's a function of proper timing, grip, and index. That's what leads to fast/accurate splits.

However, I think lower bore heights do help, but not for the reason most people assume. I think factors like low bore-height, lightened slides, tuned ammo (typically heavier bullets w/ fast powders) help since the reduction in how high and how fast the sights lift aids my shot calling and sight tracking (not my splits!).

The more "flat" I can make my guns shoot, the easier and more accurate my shot calling and sight tracking becomes. The more violent the action is, more is going on visually.

The differences are very minor, but can be noticable if shooting an El prez or bill drill or a steel challenge stage. It would, however, be one of my last considerations in choosing a pistol (either for games or more "practical" uses). If person A beats person B in a shooting contest, I don't think we could say victory was won or lost because of bore height.

Just my 2cents.

-rvb [USPSA Master]

Spot on. As proficiency increases, effect decreases. I really don't care what pistol a person prefers and says they're a better shooter with. If that's what makes you feel good, go for it! Just don't try to sell me on your "better" selection if I'm watching you shoot slower and less accurately. :)

IndianaBoy
10-07-13, 14:06
I doubt HKguns is one of them. But hey he can meet me at the Ft. Benning match this year and show me what he's got. At the last major match I was at I finished in the top 20% of my division.



What division?

warpedcamshaft
10-07-13, 14:12
What division?

It looks like Alaskapopo was banned... so he will obviously not be able to answer your question.

WickedWillis
10-07-13, 14:22
Wow. Dude had over 7K posts and he got banned for getting into an argument (he was in the wrong, I know.). Watch the comments I guess?


It looks like Alaskapopo was banned... so he will obviously not be able to answer your question.

glocktogo
10-07-13, 15:54
Wow. Dude had over 7K posts and he got banned for getting into an argument (he was in the wrong, I know.). Watch the comments I guess?

1st rule of Ban Club. You don't talk about Ban Club!

FWIW, no word on whether it's temp or perma. He may or may not be back. As much as we don't want to at times, we should all probably mind our P's and Q's a little better. :)

WickedWillis
10-07-13, 16:00
Fair enough.


1st rule of Ban Club. You don't talk about Ban Club!

FWIW, no word on whether it's temp or perma. He may or may not be back. As much as we don't want to at times, we should all probably mind our P's and Q's a little better. :)

C4IGrant
10-07-13, 16:08
I dropped off this thread when it went full nerd. Now that it's swung back a little from theoretical physics and more towards actual shooting, I'd make the counterpoint that it's merely a function of training time. Delta has to make training judgements based on practical concerns. However, were they all GM's or Masters (in both rifle and pistol), in what way would that effect their combat efficiency? What I've always stated is that firearms proficiency instilled through the rigors of competition has nothing to do with tactics. It does however free mental capacity to focus on tactics, as the shooting portion of the equation will be subconsciously ingrained and take care of itself. :)

There is so much more that goes into being a SEAL, Ranger, SF, Delta, etc etc than shooting. It is nearly impossible to be a "Master" or "Grand Master" at everything. So what happens is that they establish a set of standards. If you can pass them, you are "combat effective." Would becoming a better shooter help? Of course. Do "gun games" really make that much of a difference (when you are training properly)? I don't think so, but is up for discussion in another thread.

I do agree with you that if the "shooting part" is all figured out, then the person can focus on the tactics side. As an example of this, guys that attend home defense or CQB classes (that aren't good shooters) fall apart. They are so overwhelmed with the shooting part that their tactics suck (and vice versa). For the record, I "figured it all out" without the use of gun games. YMMV



C4

glocktogo
10-07-13, 17:00
There is so much more that goes into being a SEAL, Ranger, SF, Delta, etc etc than shooting. It is nearly impossible to be a "Master" or "Grand Master" at everything. So what happens is that they establish a set of standards. If you can pass them, you are "combat effective." Would becoming a better shooter help? Of course. Do "gun games" really make that much of a difference (when you are training properly)? I don't think so, but is up for discussion in another thread.

I do agree with you that if the "shooting part" is all figured out, then the person can focus on the tactics side. As an example of this, guys that attend home defense or CQB classes (that aren't good shooters) fall apart. They are so overwhelmed with the shooting part that their tactics suck (and vice versa). For the record, I "figured it all out" without the use of gun games. YMMV

C4

I think there are many ways to skin the same cat. Classes, matches, individual coaching from a qualified shooter, certain types of hunting (especially if the game is dangerous), etc.

The key to each and every one of them is a critical eye for picking out the good from bad and learning from both. I have several LEO's and CCW type citizens I coach. The first thing I teach them is how to effectively observe technique and critique each other. Self diagnosis is critical as well. You can't always have a coach hovering over your shoulder when you're pulling the trigger, so best you learn how to coach yourself as well. :)

Suwannee Tim
10-07-13, 17:15
Wow. Dude had over 7K posts and he got banned for getting into an argument (he was in the wrong, I know.). Watch the comments I guess?

The guy is a troll. He has baited me several times.

ruchik
10-07-13, 19:59
The way I see it, any monkey can pull a trigger, hit keys on a piano, or strum a guitar. As long as you have a solid grasp of the basics, you can turn in solid performance. But it's the people who have practiced for so long, or who have genuine talent, that can turn the skill into an art form, because they no longer need to worry about getting the basics right. They focus purely on taking things to the next level. It's in that top 1 percent that such things as bore axis, or choice of hair on a bow, or a $25,000 baby grand piano makes a difference. That's my take anyhow.

STAFF
10-07-13, 21:15
Please refrain from discussing why or why not someone was banned in a technical thread.


If your post is gone, it added nothing to the topic.

AKDoug
10-07-13, 23:52
The low bore axis on a Glock causes me trouble because my trigger finger has to go into an unnatural downward angle to operate the trigger. A Grip Force Adapter increases the bore axis almost to the point of a 1911. On a 1911, the web of my hand, the gun's trigger, and my trigger finger are in more of a straight line. Oddly enough, I am carrying and training with a Glock because the positives outweigh the negatives for me at this moment. I am flat out faster with an XDm, but speed is not everything when choosing a pistol to carry every day.

m4brian
10-08-13, 09:35
I think the problem you state with the Glock is NOT about bore axis, but about the hump and shape of the grip. The angle is not as 'natural' as in a 1911, CZ, HP, M&P, etc. etc. For me the GFA makes it even better for the bore axis, but corrects the hand position quite well. The GFA is a NICE $20 fix. Otherwise it is a $200 fix with integral beavertail.

Muzzle flip and your ability to control are a function of many things, but in general bore axis makes sense as a major contributing factor.

DanTSX
10-08-13, 20:13
There is a lot of good info in this thread. I do not think there is one final answer on the subject though. I feel that bore axis is indeed a factor that affects the physics of how a pistol reacts to discharge and recoil force and motions. However, it is not the only factor. And it will all depend on the shooter and their ability to adapt to the gun.

I have to say that from a perspective of obtaining a sight picture and recoil control, that the Glock and the S&W M&P are two pistols where bore axis is the least of a factor. While the Glock is actually lower than the M&P, the M&P certainly has less felt recoil and seems to get back on target faster for me. However, the Glock's "hump" has always aided me greatly in control. On the other hand, I find that the Walther PPQ is a little punk, but am not sure that Bore Axis is the leading contributor to that.

Ultimately, the shooter will have to try a number of guns and consider all features and attributes. If the gun that fits their requirements has a higher bore axis, it shouldn't be any reason to avoid that gun. However a lower bore axis certainly is going to be a factor in their favor all other things being constant.

TiroFijo
10-09-13, 06:14
Just for discussion sake, check this video:

http://www.youtube.com/watch?v=WOirbcsCQ1o

The cycle time is a function of other variables (recoiling mass, spring rates, length of cycle, effect of cocking hammer, etc.).

There is no doubt that a higher bore axis results in more sobreelevation at full recoil, and lost of the sight line for a longer time. How much these differences really affect shot to shot time is deabatable, and how much it really counts in real life shootings even more.

Hope this won't get me banned! :stop: :thank_you2:

Arctic1
10-09-13, 07:07
I have posted that twice already ;)

montrala
10-09-13, 07:09
Hope this won't get me banned! :stop: :thank_you2:

You are just late to the party. Go back to page 3 and read posts #53 to #61.

TiroFijo
10-09-13, 07:19
You are just late to the party. Go back to page 3 and read posts #53 to #61.

Wow! SORRY even worse than that, I've read it and forgot it... repeating myself or another poster's is a sure sign that this topic has been debated to death for me.

HKGuns
10-09-13, 17:31
Wow! SORRY even worse than that, I've read it and forgot it... repeating myself or another poster's is a sure sign that this topic has been debated to death for me.

Ummmm, there's been worse in this thread for sure! :) Probably just best to let it sink to the bottom now.

foxtrotx1
10-12-13, 12:45
I'd just like to say: Shoot the gun you are most confident with, no matter it's bore axis. Confidence is key. If you like your weapon you will shoot better than something that doesn't fit you personally, but "theoretically" is "better." I shoot a 92 :D

threeheadeddog
11-03-13, 18:46
I only read the first 3 pages...

I would argue 2 things

1. Bore axis does effect height of front sight during recoil(the only measurement that matters and that only verry little), but comparing two pistols based on that is a long-winded waste of time that has so many variables that you have to do weird math to try and make two pistols with widly different dimentions try and compare with each other. This is also really way less important than the actual movement of the front sight(time, tracking, ect).

2. I would bet good money that most people have no where near the experience or rounds fired through a pistol(and I mean real, intentional, training/practice rounds fired) to ACTUALLY SEE THE FRONT SIGHT THROUGH THE RECOIL CYCLE. I know it sure as hell took me a while before I could do it and unfortunately it is a perashible skill that with ammo prices being what they were for the last 9 months I need to work on it yet again. IMHO if you cannot see the front sight through the ENTIRE RECOIL CYCLE you have no business commenting on the benifits or lack of benifits that anything has on the recoil cycle.

pat701
11-03-13, 19:00
I prefer to shoot/own a SIG!!

YVK
11-03-13, 19:17
There is a considerable debate whether seeing sights throughout the entire cycle offers any benefit over seeing only sight lift and return. Otherwise, I agree, three-dog.

threeheadeddog
11-03-13, 22:16
I wont comment on the sight lift and return vs full cycle except to say that in my personal case I went from
-seeing sight, pulling trigger, loosing sight, seeing sight settle

to

-seeing sight through cycle

I dont personally remember a tweener phase where I was seeing it rise and fall and loosing it in the middle but honestly I havent shot a pistol in 3-4 months and maby that is all I actually see. Whatever the case I just bought several 100 round boxes at wal mart and will be getting back into the swing of things shortly.

foxtrotx1
11-04-13, 00:09
This argument is all well and good, but why not just go out and shoot instead of typing? Practice makes ab bigger difference anyway.

Rinspeed
11-07-13, 20:02
I shoot all sorts of different pistols and shoot most of them pretty well. Some better than others, but that is primarily because I shoot them more often.

High Bore Axis = The primary excuse used by poor or inexperienced shooters to explain their lack of practice and/or adaptability. Or, the excuse used to denigrate an otherwise perfectly good pistol. (It's reliable, accurate, comfortable....Oh, but it has a high bore axis so it isn't worth $hite.)




I always thought there was quite a bit of truth to statements such as this. Put enough time into it and it doesn't matter if you're shooting the latest and greatest or a 50 year old S&W model 10. When discussing issues such as this on the errornet you have to remember that to some shooting 2,000 rounds a year is a lot. To others that is just a month or two worth of practice. :confused:

Mjolnir
11-16-13, 08:42
There is one aspect that some are not addressing.

"Soft" shooting HKs and Sig P226s are perceived soft BECAUSE of the muzzle flip.

You x amount of force per caliber chosen. Period.

That energy must be dissipated by recoil.

The recoil impulse is a COMBINATION of:

1. Muzzle Flip - a function of slide mass, recoil spring assembly and the slide peak velocity or acceleration

The net effect is a MOMENT about the firing hand in line with the index finger.

2. "Push" directly rearwards which is also a function of the linear components about the center of gravity of the pistol and the holders shooting hand.

Each firearm will have a combination comprising some percentage of both.

If by what one means as "soft" I posit the pistol has less rearward linear movement and more muzzle flip.

I noticed this when transitioning from a P226 to a Glock 17: more PUSH against my hands and less muzzle flip with the Glock.

Just my observation.


-------------------------------------
"One cannot awaken a man who pretends to be asleep."

TiroFijo
11-16-13, 16:41
[QUOTE=Mjolnir;1795248]There is one aspect that some are not addressing.

"Soft" shooting HKs and Sig P226s are perceived soft BECAUSE of the muzzle flip.

You x amount of force per caliber chosen. Period.

That energy must be dissipated by recoil.

The recoil impulse is a COMBINATION of:

1. Muzzle Flip - a function of slide mass, recoil spring assembly and the slide peak velocity or acceleration

The net effect is a MOMENT about the firing hand in line with the index finger.

2. "Push" directly rearwards which is also a function of the linear components about the center of gravity of the pistol and the holders shooting hand.

Each firearm will have a combination comprising some percentage of both.

If by what one means as "soft" I posit the pistol has less rearward linear movement and more muzzle flip.

I noticed this when transitioning from a P226 to a Glock 17: more PUSH against my hands and less muzzle flip with the Glock.

[QUOTE]

The slide+barrel peak acceleration and velocity occur when both are recoiling together, before unlocking. At this moment the recoil spring (and mainspring if there is one) are strarting to compress and there is very little recoil felt by the shooter. The bulk of the recoil is felt, and the bulk of the sobreelevation due to the torque on the wrists occurs, when the slide hits the frame at the end of the recoil cycle.

MistWolf
11-16-13, 21:17
Actually, recoil starts transferring to the shooter even before the slide hits the end of it travel. Recoil is felt as soon as the spring starts being compressed and more when the barrel stops it's travel. The barrel does not unlock until it does stop and the slide continues rearward

TiroFijo
11-16-13, 21:37
This is true, but when the barrel + slide start their rearward travel, the only force acting on them is the recoil spring (and hammer spring via the hammer). The force in the recoil spring is almost constant due to the small compression difference, so there is not much reaction felt in the hands to the recoil impulse originated by the bullet + podwer mass moving forward.

After some distance the barrel unlocks (about 0.2" in a 1911) , and after this hits the frame (in the case of the 1911) or arresting device (like the slide stop in the CZ75, etc.). Now there is some more momentum transferred to the hands via the frame, but the barrel mass is much smaller than the slide's and that's the reason why most of the recoil is felt when the slide hits the frame at the end of its travel.

Arctic1
11-17-13, 03:37
Then how do you explain how a revolver recoils in the exact same manner, with no reciprocating mass?
Or that a compensated gun exhibits less muzzle flip/muzzle rise, while still having the same mass reciprocating for each shot?

I *think* that if you took a semi-auto handgun, locked the slide in place and fired a round, recoil characteristics would not be much different.

TiroFijo
11-17-13, 06:07
Artic, you "feel" the recoil in a revolver VERY differently (as I said before in this same thread): "In a revolver it is different, there is no phase of "cushioned" recoil and the higher bore over the hand produces more muzzle flip, and from the very beggining. This is the reason why the zero with a revolver (specially a magnum) is shooter dependent, since how tight and high you grip the gun makes a noticeable difference. This is also the reason why the barrel is pointing DOWN when you align the sights on a level target at 25 yds."

If you locked the slide in place, a pistol would behave just like a revolver, with much more momentum transferred to the wrists from the very moment the bullet accelerates due to the rigid interface.

In a compensated gun there is less muzzle flip due to the reaction to the blast directed upwards, and this effect lasts a little longer after the bullet leaves the muzzle. This downward force countereacts the effect of the slide hitting the frame at the end of the rearward stroke.

Arctic1
11-17-13, 06:59
Yes, but I am talking about the cause of muzzle flip.

I do not think that the slide stopping is the main cause of muzzle flip; it contributes, as it is a factor in a change of CG as well as imparting a force to the gun-hand "system", but the main factor.
My reason for this is that a revolver does the same as a semi auto handgun during recoil, thus pointing to another factor. I think that secondary recoil plays a much larger part.

Muzzle flip occurs due to the followng:

Recoil forces acting rearward through the boreline
Resistance to these forces by the shooters points of contact (pistol grip)
Height difference between center of boreline and center of point of contact, moment arm
Recoil forces and resistance operating over this height difference/moment arm, results in torque/moment causing the muzzle to flip up.

And I understand that a revolver "feels" differently during recoil than a semi-automatic pistol, the same principle as a bolt action vs semi auto rifle. This has to do with the presence, or lack thereof, of a recoil/action spring, spreading recoil forces out over a longer period of time.

If you have two guns; 1 revolver and 1 semi-auto, and they both weigh the same, shoot the same caliber at the same velocity, recoil energy will be identical. Recoil perception will be different, but the energy is the same.

My point though, is that muzzle flip will occur regardless of reciprocating mass. If that makes sense.

TiroFijo
11-17-13, 07:34
Yes, but I am talking about the cause of muzzle flip.

I do not think that the slide stopping is the main cause of muzzle flip; it contributes, as it is a factor in a change of CG as well as imparting a force to the gun-hand "system", but the main factor.
My reason for this is that a revolver does the same as a semi auto handgun during recoil, thus pointing to another factor. I think that secondary recoil plays a much larger part.



As said before, get some high speed film (50,000 frames per second or more) and you will see what I said, moment by moment...

MistWolf
11-17-13, 10:40
The slide stores some of the recoil force which is transferred to the hand and the end of it's travel. If the slide were locked into place, there would still be muzzle rise from the recoil, just that the recoil forces would be transferred all at once, not piecemeal. All the moving slide does is delay when those recoil forces are transferred.

One factor is that the arm (leverage) changes for that portion of the recoil force because the slide has changed location. The change in arm could have an affect on muzzle rise

SteveS
11-22-13, 10:42
I am sure there must be some difference but I have shot both a Glock and an XD both 9mm and almost the same 4" barrel and darn if both pistols don't fix my jerking of the trigger and improper grip and stance problems!!!