View Full Version : Crimping Non-Cannelured Bullets
Hey all,
I am trying out some Hornady .224 75 gr MATCH BTHP bullets for use in my BCM M16 upper. I have a Lee FCD but do not know if it is necessary to crimp or is the neck tension enough for an autoloader with non cannelured bullets? I full length resize with a Redding 223 Rem FL die. I've heard from some that a very light crimp is recommended and from others that no crimp is necessary at all. So what say you?
Also if I were to crimp, how will this affect the amount of powder used due to the slightly increased pressures? Hornady's page on the 75 gr BTHP cites a max load of 24.1 gr RL-15 with the load prior to that as 23.3 gr RL-15.
Thanks.
I dont crimp any of the non-cannelure bullets, doesnt mean you cant. I havent noticed any side affects of it.
Hey all,
I am trying out some Hornady .224 75 gr MATCH BTHP bullets for use in my BCM M16 upper. I have a Lee FCD but do not know if it is necessary to crimp or is the neck tension enough for an autoloader with non cannelured bullets? I full length resize with a Redding 223 Rem FL die. I've heard from some that a very light crimp is recommended and from others that no crimp is necessary at all. So what say you?
Also if I were to crimp, how will this affect the amount of powder used due to the slightly increased pressures? Hornady's page on the 75 gr BTHP cites a max load of 24.1 gr RL-15 with the load prior to that as 23.3 gr RL-15.
Thanks.
I would put a crimp on it. A taper crimp just pushes the neck up tight against the bullet and will work without a cannelure. I have some non-cannelure 75gr BTHP from PRVI and have not loaded them yet but will be doing this on them
See the recent Kaboom thread that appears to have happened due to setback... I'd rather be safe than sorry and so I do my best to make things as safe as can be.
I'd rather be safe than sorry. I don't think that this sort of crimp should affect pressure in any meaningful way but that is just a guess. Check for signs of pressure etc etc etc like you would when working up a load.
I would put a crimp on it. A taper crimp just pushes the neck up tight against the bullet and will work without a cannelure. I have some non-cannelure 75gr BTHP from PRVI and have not loaded them yet but will be doing this on them
See the recent Kaboom thread that appears to have happened due to setback... I'd rather be safe than sorry and so I do my best to make things as safe as can be.
I'd rather be safe than sorry. I don't think that this sort of crimp should affect pressure in any meaningful way but that is just a guess. Check for signs of pressure etc etc etc like you would when working up a load.
+1 - You are begging for a KB if you do not taper crimp. Your reloads will also go bad pretty quick to if you live in a high humidity area.
How to do a taper crimp with the Lee FCD?
How to do a taper crimp with the Lee FCD?
I have not used the Lee FCD but it should crimp (its in the name). I would assume you just screw it down to increase the crimp. Does it contain instructions?
I have a few around here on the shelf somewhere but have never used one myself (yet).
Yeah directions just say to screw it down little at a time to experiment with crimp. What I really meant was how much of a crimp is necessary? I'd rather not be damaging the bullet with a crimp. I wonder if Molon has a write up on this...
thanks for your help so far
Yeah directions just say to screw it down little at a time to experiment with crimp. What I really meant was how much of a crimp is necessary? I'd rather not be damaging the bullet with a crimp. I wonder if Molon has a write up on this...
thanks for your help so far
You're not damaging the bullet anymore with a crimp than a similar bullet, which has a factory cannelure applied, is damaged.
The Lee FCD doesn't apply a taper crimp, it applies a unique style crimp that is even all the way around the bullet from the top of the crimp to the bottom of the crimp (a taper crimp crimp crimps harder at the top than the bottom). I recommend you experiment with crimp pressure, but in my experience you don't need much. Start out with half the pressure that Lee suggests in their directions and adjust die in small increments and test for accuracy. If you can get above your press and look down into the die you can see the collet squeeze the bullet and apply the crimp. You can get a sense when you're starting to apply a crimp and when you've gone overboard.
I have mine adjusted to apply the light-moderate crimp. It's enough to guard against bullet setback but not so much to do major harm to the bullet. IIRC, crimp pressure is slightly less than what Lee includes in their directions, but honestly, it's been a couple of years since I set it so I could be off a bit in my recollection. I know that I can't get a seated & crimped bullet to budge by pressing a loaded round into my bench, bullet down, with many lbs of pressure pushing aginst it. But this has as much to do with ensuring proper neck tension exists, and that's a function of having your resizer set up properly. This equates to polishing your expander ball down or using the correct bushing. Crimp pressure is not a suitable workaround for inadequate neck tension, and I polished my expander ball down to ensure about .003" difference between resized and loaded rounds.
I tried working up some tonight. I do not have the hornady manual to see exact load data for the 75 gr bthp. So I used the sierra 77 gr mk data of a min charge of 22.3 gr rl-15 and just tried 22.4 gr and had an accuracy of +.2 gr from the goal of 22.4 with most being exact 22.4 gr. I think I have just been spoiled by the scales I use in college for chemistry. The hornady powder dispenser on the lnl AP is about as precise as it's going to get. All brass were trimmed to 1.750". Coal varied up to 0.003" below 2.260".
With the lee fcd I set to lee's instructions and ended up backing off a smidgen. The petals of the crimped would collapse down just a slight amount on the neck. I tried forcing the bullet into the case witb a good amount of muscle and it would not budge. Success so far until I test them. I made some with crimp and some without. Although because of inconsistencies of the powder, brass quality, bullet mass, and etc. Just now to buy a chronograpgh.
I have been using the Lee FCD on all of my semi-auto caliber rifles for years. You don't need a hell of a lot of crimp and it works great.
If you're concerned about it, buy military ammo. The bullets will be crimped into a cannelure and the bullets will be "Glued" or asphalted into the neck.
If you're shooting for accuracy you'll be loading with proper neck tension -- usually with a carbide size die (like a Redding S-die) specifically for your weapons, sizing the case neck 2 to 3 thousandths of an inch smaller than bullet diameter.
Reloaders using standard full-length sizing dies with no consideration for bullet diameter, with large buttons on their decapping rods, shooting in chambers on the fat side of SAAMI or MILSPEC / NATO risk bullet set-back. Setback bullets may raise your chamber pressures to unsafe levels.
Crimping a match bullet with either an excessive taper, without a cannelure, or with a Lee Factory Crimp Die risks separating the lead core from the copper jacket, making a bullet that wobbles about its axis. Unnoticeable from muzzle to 200 Meters (where most folks shoot) but will definitely be apparent at longer ranges (especially if trying to take precision shots with magnification).
Buy good reloading books, get the proper tools, and load with the proper dies and components and you'll never have to worry.
Go around blind and you're always guessing and worrying. 99% of the M4/M16/AR shooting crowd will never notice the difference.
moneymaker
02-07-10, 20:06
i use the lee fcd on every auto rifle load i use,bullet push back is not your friend
Thanks for your insight, sinister. I found the coal was too long at 2.260 for magazine length and set them back to 2.250" with an observed 0.003" variation. I'm guessing it has to due with slightly non uniform meltplats on the loose packed Hornady 75 gr bthp or likely due to my seater die not being comp' grade per say(standard 223 2 die FL redding).
With a new batch I tried 2.250" coal with all cases at 1.750" oal +-0.001". 22.8 gr R-15 with +-0.3 gr observed variation from the powder drop. Seating die was turned out a full turn to avoid the integrated crimp on the redding seaters. I set the Lee fcd to a very light crimp(looked like it was just doing a little more than an all around touch) and checked the strenght of it by putting some marker on the neck and saw light marring of the color. Primer pockets were just cleaned with a brush.
Now about neck tension; is a special tool required or can I use standard calipers? Right now I'm mostly just interested 0-200m target and small-medium game hunting. That and I don't expect too much better than slightly sub moa from this upper. Good enough for small whitetail and feral hogs around here though. I'll invest in a single stage, a better scale, and some competition dies for longer range work once I have rifles more accurate than my K31s.
I'll try getting to the range to try these out scoped at 100 m. Any recommendations for a good chronograph?
Any recommendations for a good chronograph?
I use the CED. Do your own research but it is used by many many professional organizations.
If your sizing die is working correctly you do not need to crimp any bullets in the 223/5.56. Load the round, put the bullet on a piece of wood and put some force on it, a bunch, like use some ass on it. If it moves, you need to get a sizing die that sizes the case more or mic your bullets.
If you are having double feeds and cartridge stoppages that are pushing bullets into the cases you have other problems and crimping bullets is not the solution.
BTW, the one set of dies that I used that would not size the case enough to hold the bullets was made by "Lee Precision". Those two words should never be used together. Lee's stuff is junk and you need to be told.
I use Lee FCD on my AR handloads with good success on Hornady and Nosler OTM's without a cannelure. I've stripped no jackets and I put a pretty heavy crimp on the rounds. The ride from the mag to the chamber is not a gentle one and I see it as insurance. I have been unable to drive any bullets deeper in the case with considerable force. I load very warm rounds as well.
I see a little variation in the COL using OTM's in 223 and 308 measuring with calipers.
Now about neck tension; is a special tool required or can I use standard calipers? Right now I'm mostly just interested 0-200m target and small-medium game hunting. That and I don't expect too much better than slightly sub moa from this upper. Good enough for small whitetail and feral hogs around here though. I'll invest in a single stage, a better scale, and some competition dies for longer range work once I have rifles more accurate than my K31s.
Standard calipers are fine. I polished my exp ball to achieve .003 delta between resized and reloaded rounds.
I used to use only RCBS dies, but after several stuck cases and broken deprimer pins and other fustrations am worming my way out of them. I have used Lee dies since they first came out with NO issue over all these years. If I happened to hit a hard/berdan primer the Lee die would push up the decaping pin. I would tap the pin down and tighten the decapper. Simple, no cost, and it works great. I used to shoot long range matches, at Fort Benning, and have NEVER had an accuracy issue with the Lee dies or the the tapered crimp die. That was both 5.56 and 7.62x51.
I have friends shooting the, 6.5 Grendel, who get sub MOA all the way to 1,000 yards with NO issues. They too use Lee dies. :D:D:D
All hollow point bullets will show length variation unless you uniform trim the meplats (really more work than it's worth since you're using a +/- .3 grain powder variation rather than trickling charges).
Factory dies should be OK if the farthest you're shooting is 100-200 yards and you're shooting woodchucks to deer.
Measure your bullet diameter with your calipers; select a die that will neck size your case mouth opening to .002 to .003 smaller than bullet diameter (your brass will squeeze down, but will also spring back out about a thousandth due to the elasticity of brass).
Any crimp defeats the purpose of an accuracy load for extended ranges. My guess is you won't be able to discern much difference at 100-200 yards. The proof will usually show at 300 and out.
There are gages to check force required to seat, but your best gage will be your hand (you should be able to feel the difference between bullets that seat harder or softer than the mean).
A precision/match shooter is going for consistent, small 10-shot groups centered about an aiming point (the X-ring or center-of-mass of any exposed part of a hostile target). An occasional hiccup won't bother a guy shooting at groundhogs or coyotes, but it can lose a precision shooter a match or a firefight -- with other consequences.
If you're going for big money or bragging points (i.e., benchrest or turkey shoots for prizes) nobody crimps. Crimping is to minimize the possibility of mis-feeds with added pressure and safety risks.
Your 22.8 charge seems a little light, but I will err on the side of accuracy and consistency over velocity. The Lyman manuals usually reflect slightly higher charges than both Hornady and Sierra.
A BCM is a good barrel and MOA to slightly better is very do-able. Try to minimize your variables.
Thanks for that. I'll check what neck tension I'm getting.
So do you guys crimp your primers also? :D
I think part of the equation is what sort of gun you are shooting. I won't claim to be any sort of expert but I would not crimp rounds shot from a bolt action. I would on those shot from a semi-auto, at least of the AR platform type but probably all military semi-autos. I'd rather be on the safe side and I am not shooting benchrest with that sort of gun.
RDC, NO most don't crimp the primer. However, If you plan to store the ammo for a long time, or expect to be in a very moist environment, use you wifes fingernail polish on the primer and around the primer. It does not take much so be frugal. And a very slight tapered crimp will NOT harm a thing.
Some very famous High Masters just buy WW primed cases, run the stuff through a Dillion with 69 or 77 Sierras using RL15 then go shoot for the win. They may single stage the 600 yd ammo and check for run out but, I doubt it. They do not crimp.
Crimping bullets and trying to blow up your gun to reach velocities with high pressures is just plain silly to me. If you need to go farther and flatter get a larger caliber, if you need more accuracy than an AR, get a custom bolt rifle.
John Feamster's & Glen Zediker's books have good AR reloading information. Buy them.
The best overall reloading article for 223/5.56 was a huge test of powder & bullets by Derrick Martin & Barret Tillman that appeared in Precision Rifle. They also have a book and I'd bet it is good but, I do not own Derrik & Martin's book so I do not know.
I was kidding about the crimped primers thus the :D.
I'm sort of a new reloader (2 yrs) but I've used the LFCD on all my rounds for semi-autos. I started at the lowest powder charge and worked up incrementally and have gotten good accuracy.
Not crimping may be okay to but I don't trust it in semis.
Not crimping may be okay to but I don't trust it in semis.
Okay. What have you seen that indicate non crimped cartridges untrust worthy? I contend it's a myth based on a perceived fear, not an actual one. It's a band aid for bad dies. Mainly LEE.
From what I understand, crimping simply tries to compensate for poor neck tension as a result of poor dies and an improper neck expander job on bottleneck cartridge dies. In a sense of physics, a uniform neck tension equivalent to the tension created by the crimp in a much smaller area is simply going to provide more consistency.
I would like to test the real effect of crimping vs not crimping but unfortunately as sinister said I have too many variables that could account for poor accuracy namely the rather varied powder charges due to using a powder measure in progressive mode without checking individual charges past my powder cop die. Oh well. I'm learning a lot. This is my first time reloading.
Okay. What have you seen that indicate non crimped cartridges untrust worthy? I contend it's a myth based on a perceived fear, not an actual one. It's a band aid for bad dies. Mainly LEE.
Nothing.
Just for my education, do any manufacturers not crimp?
Okay. What have you seen that indicate non crimped cartridges untrust worthy? I contend it's a myth based on a perceived fear, not an actual one. It's a band aid for bad dies. Mainly LEE.
this guy disagrees.
http://www.m4carbine.net/showthread.php?t=46325&highlight=kaboom
another thing is that not all brass is created equal, and it changes over time. Yeah. you can turn your ball down till it's perfect, but there's no gaurantee that the elasticity is going to be the same on every batch of brass. nor is it going to be the same on the same brass from one round of loading to another.
autos in general mash the meplat when they cycle. It doesn't make a difference if you're working a 45 acp. but if you're working a 357sig then you absolutely have to crimp. no amount of neck tension is going to keep that bullet from setting back with so little neck. it's going to vary from cartridge to cartridge.
I'm not saying you always need a crimp but to say that you never need a crimp sounds borderline irresponsible.
http://www.m4carbine.net/showthread....ghlight=kaboom
He was using a neck bushing die set for .002-.003 neck tension in a progressive machine. I personally would never neck size only for any semi-auto. I use a cartridge micrometer and set the shoulder back at least .002 with a full length sizer die. Like I said earlier. Properly assembled hand loaded ammunition does not require a crimp. Test it. It should not telescope bullets if properly assembled.
The way I see it there are two problems (1) neck sizing die with too little tension and (2) progressive machine. I would agree with his first assumption that it was a squib load that caused that. It could just as well be a slam fire because the case was not sized sufficiently. Who knows?
I do not believe that a telescoped bullet would cause that kind of over pressure to wipe out the rear of the case. Not saying it didn't happen because strange things happen when you do not do things incorrectly.
As I said earlier crimping is a band-aid for a more serious problem. Crimp if you like, just don't say you have to crimp or your rifle will explode. Or don't say you have to use magnum primers or your rifle will explode.
Confession time:
I discovered the hard way a taper crimp on a non cannelured bullet won't help prevent setback anyway. Neck tension is everything. Having said that it probably does not hurt either as long as it's light and the brass has been freshly trimmed.
Due to the shortage of Black Hills match ammo just before Y2K, I was forced to reload my 3-Gun accuracy load at the time - a 68 grain Hornady that I had previously proved to be a pretty close duplicate of the similar, and my preferred, BH loading. I bought a batch of fully processed LC brass and ran 1,000 through the Dillon 1050 without re-resizing. I had used the same supplier before, but probably did a second resize before loading.)
Being in a hurry was a Big Mistake. I later found that a good number, maybe 10% or so, of the pre processed brass had weak neck tension and were setting back significantly on chambering. It's a wonder I did not blow myself up.
I went back and put a hard taper crimp on them and it did not help a bit. Gave em all away to someone willing to pull the bullets; all except for one 50 rnd box I still have on the shelf as a reminder.
Nothing.
Just for my education, do any manufacturers not crimp?
Still waiting on an answer to this question???
Redhat.... they ALL use a taper crimp. Which is very similar to the Lee Taper Crimp. Just don't overdue it, it DOES work. I have a friend with a 6.5 Grendel who shoots up to 1,000 yards with a Lee Taper Crimp. He shoots sub MOA so WTF??????
In my opinion, and a LOT of others, a slight crimp using the Lee dies prevent set back and the chance of high pressures. In a bolt rifle or single shot it is NOT necessary. Military Ammo has bullets with a "crimp" grove on them. Why??? They have learned that setback can be a "bitch."
Military Ammo has bullets with a "crimp" grove on them. Why??? They have learned that setback can be a "bitch."
First of all the military does not have ammo manufactured for semi rifles. They have ammo manufactured for machine guns.
I'm looking at M72 LOT LC 12253 and there are no crimps. I believe that M118 and M852 Match ammo was never crimped also. I have Greek M2 and there is no crimp.
I just talked to some F-Class single shot bolt gunners. They just push the bullet in the once fired case then go shoot. They neck size only when there is no bullet tension. They use 284 Win. There are no 6.5 Grendels on the line BTW nor have I ever heard of a 6.5 Grendel winning anything long range 1000 yards. Enlighten me if I'm wrong.
Have a nice day and crimp if you like, just don't say it has to be crimped or is an accuracy enhancer. Google Ed Harris and crimp, I think you might know who Ed Harris is. Right?
BTW, I examined all the commercial and military ammunition I have. All LC M2 is crimped, Fed, Rem & Win 7mm mag is crimped, Win 375 H&H is crimped. This is now a research project because I cannot believe all of it is crimped. I just can't imagine 6mm Norma BR crimped from Norma.
What relevance does reloading for an F Class bolt gun have to do with the AR15?
What relevance does reloading for an F Class bolt gun have to do with the AR15?
There are multiple claims (including LEE ) that crimping promotes accuracy. It does not as the F Class shooters would be crimping for 1000 yard prone if it did. The previous poster stated 6.5 Grendel at 1000 yards crimping with MOA performance. I say congrats and see you at camp perry.
Since you've used BH match, was it crimped?
Since you've used BH match, was it crimped?
I honestly don't recall, but possibly not been since (I'm fairly sure) it was a non cannelured round. I'm a big believer in good bullet pull over everything else. The part that struck me about the F class guys reloading without even neck sizing, is the part that cannot be applied to loading for the A/R.
Is there a benefit to using non-cannelured bullets?
There are multiple claims (including LEE ) that crimping promotes accuracy. It does not as the F Class shooters would be crimping for 1000 yard prone if it did. The previous poster stated 6.5 Grendel at 1000 yards crimping with MOA performance. I say congrats and see you at camp perry.
Since you've used BH match, was it crimped?
Who makes these "multiple claims" that crimping promotes accuracy you speak of?
Are you a SME on reloading/handloading? Perhaps you could provide a little info on your background and experience so those you are advising know where your coming from.
I just talked to some F-Class single shot bolt gunners. They just push the bullet in the once fired case then go shoot. They neck size only when there is no bullet tension. They use 284 Win.
I know a couple of F class guys - they use 30" bolt guns in .260 Improved that one of them developed - pretty serious guys and good enough to shoot internationally, btw. I'll be very surprised if they ever reload without neck sizing. I'll have to ask next time I run into them at my club.
Who makes these "multiple claims" that crimping promotes accuracy you speak of?
Are you a SME on reloading/handloading? Perhaps you could provide a little info on your background and experience so those you are advising know where your coming from.
You have got to be kidding me. Read the thread.
One more time. I DO NOT GIVE A SHIT IF YOU CRIMP THE NECKS ON EVERYTHING INCLUDING THE FUCKING CAT. GOOD LUCK!! GOT IT? :D
At my age (50), with my experience, I have found that you cannot give advise to anyone with out a bunch of BS. So, I grow tired of the BS and will let the ignorant lead the ignorant. :(
rdc0000,
Not trying to offend, I just prefer to know who I'm listening to and what their background is.
I think that's fair before I follow someone's advice.
I loaded up some without crimps and found with neck tension alone I could not shove the bullet back in even with a large amount of force pressing the round nose first into my bench. I measured neck tension to be .004" on the centurion m193 brass I was resizing in my redding fl die. I'm going to the range in the morning to try. Then off to the reloading shop to grab a powder trickler and funnel to help isolate the variables on the next batch.
I loaded up some without crimps and found with neck tension alone I could not shove the bullet back in even with a large amount of force pressing the round nose first into my bench.
I am not sure this is a valid test. I am not a physicist nor a mechanical engineer, but the impulse of a bullet being slammed out of a magazine forward up the feedramps in a fraction of a second is way different than a steady but relatively heavy force being applied by you against your bench.
Take the case somehow and hit it against a piece of steel pretty hard and see what happens.
One problem in this thread is that some people are talking about loading for accuracy competitions and others for reliability in combat arms.
For me, I will be crimping, because I am loading for reliability out of combat arms. I am not loading to win a 1000 yard benchrest competition.
Apples and oranges, true -- but if you're not staking-in and waterproof sealing your primers, waterproofing the bullets into the neck, and crimping into cannelures (thus dropping your accuracy potential) you're NOT producing combat weapon ammo.
Most people on this and TOS will NEVER shoot their weapons to 300 or farther on a consistent basis. I would dare say few will ever wear out a single barrel.
I shoot. I handload because Uncle no longer buys my ammo. I hand load BETTER than MILSPEC.
If you're happy with crimping, do it (on a Dillon it makes no difference since it's the last die station). I don't.
moneymaker
02-14-10, 07:41
For auto rifles crimp PERIOD!!!!!!!!!!!!!!!!!!!!!Why ?? You dont want set back as the bullets gets beat to death going from the mag into the chamber,if you dont think so,let one slam home then take it out and look at it,Now even under neck tension ways of reloading if you got some weak brass you will not see it until you fire it and the word is COULD have issues!!!Geez not a 4 page subject just CRIMP:eek:
I agree with money maker, if you are loading for the AR-15 you better be safe and crimp. You don't have to overcrimp, just crimp.
I used to "no crimp" myself. In a match at the Central Alabama Gun Club, I had the bottom of my magazine blown out and the bolt carrier jammed......just scared hell out of me. A fellow shooter and reloader asked if there was a chance I "double charged my load." I remarked "Hell NO, I check my charges and weight every powder drop for match use." His next question was "Do you crimp?" To which I had to say "NO". NEVER again, with a semi-automatic firearm, will I not crimp. Different magazines feed at slightly different angles into the breach! I your reload hits the ramp a little off you are in for a big surprise!!! You guys do what you want but I am telling you I was LUCKY, next time (which won't happen) I may not be so lucky.
I am not sure this is a valid test. I am not a physicist nor a mechanical engineer, but the impulse of a bullet being slammed out of a magazine forward up the feedramps in a fraction of a second is way different than a steady but relatively heavy force being applied by you against your bench.
Take the case somehow and hit it against a piece of steel pretty hard and see what happens.
One problem in this thread is that some people are talking about loading for accuracy competitions and others for reliability in combat arms.
For me, I will be crimping, because I am loading for reliability out of combat arms. I am not loading to win a 1000 yard benchrest competition.
Sierra says it's a valid test..
Take a rifle/bullet combination with some chambering issues, add in a very minor case of weak neck tension and you can have major problems in a heartbeat.
From my post on this thread (edited to make it a little shorter):
http://m4carbine.net/showthread.php?t=46180
......
.............
I happened to have 5 dummy rounds (no primer or powder) on my reloading bench this morning that were used in setting overall length, function testing, etc.; four 75gr Hornady OTMs plus one 55gr Hornady FMJ. They had already been chambered in my Noveske once with no deformation of the bullet tips (but they did show some minor scratching on the side of the bullet).
I again loaded them in a mag and ran through the Noveske, then in two other rifles with with the following results:
1) Noveske Complete 16" Upper, 1x7, & Noveske Lower: No bullet tip deformation.
2) Older Colt Lower and Colt Upper Receiver with a hint of M4 type receiver cuts & 14.5 BM barrel, 1x9: no bullet tip deformation.
3) Older Colt Lower #2 and Complete BM 20" Upper, 1x9 - no receiver cuts: This was a Pisser - no bullet tip deformation, but two of the 75gr bullets were driven back into the case, one catastrophically!
3a) BM 20" upper again with new dummys (3ea 75 & 55gr): Same results - 2 out of 3 of the 75 OTMs driven back into the case - one completely! No problems with the 55s. Moderate to somewhat heavy scratches on the sides of the bullets (one chambering), no tip deformation. Fortunately I've never tried the 75gr reloads in this rifle!
1a) Noveske again with more new dummys: Loaded the same mag and chambered twice. No issues except one of the 75s actually ended up a few thou longer, (the others ended ~.0002 shorter). Light to moderate scratches on the sides (two chamberings); no tip deformation.
.....
ETA: My problems with setback (above) appear to be compounded by weak neck tension. ....!
I just ran the same tests again with brass that was sized in an RCBS die and had no setback issues in the 20" BM upper. Still, this shows the M4 barrels/receivers perform better.
I would respectfully submit that loading ammo with a mass-produced factory RCBS die that is supposed to size necks for all commercially available .223 bullets on the market to chamber in all .223 caliber rifles ever made is a crap-shoot.
If you are loading for semi-automatics or machineguns I would recommend you add a Redding S-type bushing neck-die specifically for the bullets you are loading. If you demand the peace-of-mind that comes with crimping, use a taper or Factory Crimp Die.
There is a difference between mass-produced and accuracy ammunition.
If you do shoot for accuracy (either with irons or telescopes, at extended ranges where the conversation hovers around end-of-match objectively measured scores or kills on things like groundhogs, crows, prairie dogs, and coyotes) I'll bet you won't crimp. If your shooting style does not, it won't make any difference.
MOLON on the other site has done extensive prove-it-by-shooting-it documentation. I highly recommend it as worth reading.
I don't post to threads often.......but after processing/loading "A-LOT" of brass over the last 40 + years......... have a couple observations with 5.56x45mm/.223 Rem. brass that I would like to post:
1: On case-necks......the thickness of the case-wall changes as the brass is fired and again when resized even if not "turned-down" with a cutter for uniform thickness.
2: Not all brass manufactured for one caliber has the same case-wall thickness by manufacturer.....or even the same calibers by the same manufacturer..........and again, as this is fired and re-sized (be it FL-sized or just the neck-sized) changes case-wall thickness and "tension" on the next bullet loaded.
3: One thing that I have not seen talked about here (but have seen the effects of case-heads cracking on another Board) is that with SAAMI-Specs......cases and case-heads can have different thicknesses/diameters and still be "acceptable" to SAAMI-Spec. standards of manufacture........
I have seen the results of some case-processors (Companies) trying to "roll-size" the bulged area just above the extractor-groove that usually isn't re-formed well by most FL-reloading-dies. This "work-hardening" causes "stress-cracks" and weakens the base of the case......which now, cannot withstand the presure.
4: Most reloaders do not want to take the time to measure case-wall-thickness on their brass at the necks if the cases are just to be used for practice-ammo to "blast-away".............it is time consuming. "But", with that said, they will pick up "range-brass" of unknown quality or number-of-reloadings to save money.....and process that into their group of brass-cases to be cleaned/reloaded for the next range firing. If all of your brass is mixed (?)....or of unknown number or firings even in the same case-head-markings.......bullet tension will be different. (IE: If you miss one case that had thin case-walls at the neck.....loaded this case with a light neck-tension/crimp on the bulet....it may be the "one" that sets back...casuing more pressure than that case will take.).
5: Good die-sets help, as will clean brass........and "work" your brass as little as possible for longer life.
6: Know the "lead" on your chamber.......they were not all made the same and will give you "bullet-set-back" if the bullet-design" has a longer "ojive"/outside-curve, or if you seat your bullets out of the cases farther. Set-Back during chambering of cartridge (be it from a short-lead in the chanber.....or from light bullet-tension/weak-crimp due to thin case-neck-thickness, die-adjustment) will raise pressure.
7: Pressures change from "lot-to-lot" of powder.........use a cronagraph (?-spelling)....and recheck your powder charge for that "lot" of powder often.
There are only so many things that you can check on a case, and during re-loading ammo........and when "pushing-the-envelope" for more pressure/velocity/speed.......if you miss one case (?).
My only suggestions would be to look at what the ammo will be used in/for......take what appropriate reloading-actions/checks so that you can to insure that the ammo you are making up stays withing specs. for "your" rifle(s) and chamber(s). If the ammo is going to have more pressure/velocity/speed........use the best cases that you have (or get new cases).....it's your face next to the chamber when you pul the trigger.
Check you "finished-product" to insure that it meets your needs/requirements for the weapon it will be used in.......this may require extra steps or checks. Chamber-gauges help.
If your cases are mixed/or unknown number of firings........I see nothing wrong with using these cases at less pressures/lighter loadings for "blasting" ammo....just keep the pressures down and insure that the bullets will not "set-back" for any reason.
Last.....when your cases are worn-out.......don't just leave them on the ground at the range for the "new-guy" to try to reload.....or the "Brass-Miners" to pick up for sale at the next gun-show..........recycle them for scrap. The added $$$ might help you keep firing more this next year.
Regards, RichardS in MI.
Excellent post, Blanksguy. Thanks for sharing your knowledge.
Originally Posted by shootist~
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I happened to have 5 dummy rounds (no primer or powder) on my reloading bench this morning that were used in setting overall length, function testing, etc.; four 75gr Hornady OTMs plus one 55gr Hornady FMJ. They had already been chambered in my Noveske once with no deformation of the bullet tips (but they did show some minor scratching on the side of the bullet).
I again loaded them in a mag and ran through the Noveske, then in two other rifles with with the following results:
1) Noveske Complete 16" Upper, 1x7, & Noveske Lower: No bullet tip deformation.
2) Older Colt Lower and Colt Upper Receiver with a hint of M4 type receiver cuts & 14.5 BM barrel, 1x9: no bullet tip deformation.
3) Older Colt Lower #2 and Complete BM 20" Upper, 1x9 - no receiver cuts: This was a Pisser - no bullet tip deformation, but two of the 75gr bullets were driven back into the case, one catastrophically!
3a) BM 20" upper again with new dummys (3ea 75 & 55gr): Same results - 2 out of 3 of the 75 OTMs driven back into the case - one completely! No problems with the 55s. Moderate to somewhat heavy scratches on the sides of the bullets (one chambering), no tip deformation. Fortunately I've never tried the 75gr reloads in this rifle!
1a) Noveske again with more new dummys: Loaded the same mag and chambered twice. No issues except one of the 75s actually ended up a few thou longer, (the others ended ~.0002 shorter). Light to moderate scratches on the sides (two chamberings); no tip deformation.
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ETA: My problems with setback (above) appear to be compounded by weak neck tension. ....!
I just ran the same tests again with brass that was sized in an RCBS die and had no setback issues in the 20" BM upper. Still, this shows the M4 barrels/receivers perform better.
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What powder and charge weight are you using that allows "catastrophic" bullet setback with 75s?
What powder and charge weight are you using that allows "catastrophic" bullet setback with 75s?
Those dummy rounds, as stated in my post, do not have powder (or primers).
Those dummy rounds, as stated in my post, do not have powder (or primers).
I see.
I'm not syaing it can't happen, but with 75s and standard charges, I doubt you'd ever experience setback upon chambering because of the high loading density. At least with a proper charge of Varget or RL-15, the powder takes up so much volume the challenge is getting the bullet to seat and not back out.
With ball powders and 55 grain bullets, different story. There's enough empty case for the bullet to be driven into.
Great thread, All.
OP, we must be cut out of the same fabric. (I agree, after using a balance accurate out to .0001, reloading becomes a fun game of attention to detail.)
I am also new to reloading, and in my case I am using LC brass that I cleaned, punched, swaged, hand primered. 75gr OTM Hornady, 22.7g H4895.
So I did use the Lee FCD, but on the first few rounds I didn't feel any feedback through the press and ended up using quite a bit of force. You can see on those rounds (with heavy crimp) the shape of the bullet.
My question is will a HEAVY or way overcrimped cartridge increase the pressure to the point of failure or danger?
Thanks
I see.
I'm not syaing it can't happen, but with 75s and standard charges, I doubt you'd ever experience setback upon chambering because of the high loading density. At least with a proper charge of Varget or RL-15, the powder takes up so much volume the challenge is getting the bullet to seat and not back out.
With ball powders and 55 grain bullets, different story. There's enough empty case for the bullet to be driven into.
No arguments here. I did see setback problems once with the same problem child 20" rifle and loaded ammo using 68gr BTHP bullets and W748 [ball] powder. I even rebarreled it thinking the sudden erratic accuracy I was seeing was in the barrel. The same rifle functions and shoots very well with M193 and even 63gr reloads, but obviously I can't trust it with the heavier loadings (at least not reloads).
I'm using Varget with the 75s, which is a compressed load, but they are for the Noveske.
ETA: And based on Blanksguy's post, I think I'll stay with once or twice fired brass even then.
moneymaker
02-15-10, 19:21
i will try to post up pics of what the crimp looks like when i am finished and what i have used for years on all auto rounds,not enought to cause bullet deformstion but enough to trust it to no set backs
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