View Full Version : Barrel profile and accuracy
Does the profile of the bbl make a difference in the accuracy/precision capabilities? I'm building a recce style rifle and have been shopping around for a bbl. 16" 1/8 stainless is my only requirements, trying to stay at $250 or less. So far I'm looking at Faxon, Rainier, or Ballistic Advantage.
Faxon offers a Socom and heavy fluted profile, BA offers the Hanson profile, and Rainier is a medium.
Which would be the most bang for the buck?
What is the max distance you intend to shoot? I usually subscribe to the theory of heavy diameter to fat barrels for acuracy and sustained accuracy (heat up issues) and longer barrels when you also need velocity at longer ranges.
Both for long-range precision work. Factors like weight and budget, brand, features (profile, fluting, chsmber, etc.) then start coming into play.
If 5.56, also don't forget the chanber design and I'd suggest a Wylde chambering.
Auto-X Fil
12-07-15, 15:40
Thin profiles give up accuracy in a few ways:
1) They have a more pronounced "sweet spot", which means they will be pickier with ammo. Real fat barrels are more likely to shoot any match-grade ammo well.
2) They will flex more with an added suppressor, barrel-mounted accessory, or load imposed by a sling or bipod. Proper use of a modern free-float handguard remedies this.
3) They tend to change POI with rising temperature more radically, as well as getting hot faster.
For slow fire, with a load that gun likes, with a floated barrel, great things can be achieved with skinny barrels. Check out Borden and other lightweight, match-grade hunting rifles for a perfect example.
If you want to switch up Black Hills, Federal, and whatever else, and rip off rounds quickly: the heavier the profile, the better.
Now, from that list, I'd go Ranier. Have you checked out White Oak, as well?
More info. Longest shot right now would be about 300m. I currently live in Alaska, so I can't order ammo. Anything other than run of the mill 193 or 855, PMC, etc isn't available, so I will likely be handloading.
Obviously a heavy profile would maintain accuracy through sustained fire better vs a light/pencil, but would there be a noticeable difference in say a medium vs heavy?
What about fluting? I'm reading fluting is mostly snake oil and only good for looks.
FaxonNathan
12-07-15, 19:30
Thin profiles give up accuracy in a few ways:
1) They have a more pronounced "sweet spot", which means they will be pickier with ammo. Real fat barrels are more likely to shoot any match-grade ammo well.
2) They will flex more with an added suppressor, barrel-mounted accessory, or load imposed by a sling or bipod. Proper use of a modern free-float handguard remedies this.
3) They tend to change POI with rising temperature more radically, as well as getting hot faster.
For slow fire, with a load that gun likes, with a floated barrel, great things can be achieved with skinny barrels. Check out Borden and other lightweight, match-grade hunting rifles for a perfect example.
If you want to switch up Black Hills, Federal, and whatever else, and rip off rounds quickly: the heavier the profile, the better.
A solid statement, which we echo completely. Good knowledge here!
FaxonNathan
12-07-15, 19:43
More info. Longest shot right now would be about 300m. I currently live in Alaska, so I can't order ammo. Anything other than run of the mill 193 or 855, PMC, etc isn't available, so I will likely be handloading.
Obviously a heavy profile would maintain accuracy through sustained fire better vs a light/pencil, but would there be a noticeable difference in say a medium vs heavy?
Given the available ammunition will vary across a wide range of weights, we would recommend the 1/8 twist. It will produce the least variation between your zeros across bullet types and loads.
Assuming you want to maintain a good zero without groups opening significantly during spirited shooting, below is a good rule of thumb for choosing a profile:
1. 15 rounds or less: Pencil
2. 60-90 rounds: Gov't / Hybrid profiles (like our Gunners)
3. Any more: Medium & Heavies
We would make the blanket statement that people often buy "too much barrel" for their needs, often going heavier than they really require. Most people only care about their first shots and magazines and after that point, its a moot point.
So, if we may be so bold as to make a recommendation on profile and the above assumptions, the Flame may be a solid option, given its medium-fluted barrel, stainless, etc.
However, we would also caution against stainless in extreme cold environments. Even 416-R, which is what we and the other manufacturers use is typically only rated to -40F. Just know what you are getting ahead of time.
What about fluting? I'm reading fluting is mostly snake oil and only good for looks.
Actually, fluting can be quite valuable, depending on the type of fluting and worst case-scenario, it reduces weight.
The rigidity of a barrel is predominantly determined by the OD of the barrel. Given that fluting does not reduce the OD significantly relative to the weight savings, it at the least removes weight and for when barrels get really hot, they help dissipate heat faster by creating more surface area for the metal to exhaust heat to air.
Other fluting profiles can actually help with base accuracy, given a good base barrel to start with. Spiral, our FLAME series, dimpling and other non-linear fluting patterns can, in certain instances, improve the accuracy of the barrel by working to mitigate the whip the barrel would otherwise experience. This is typically found by hand-loaders who find the "sweet spot" through detailed experimentation.
The fact that it looks cool is just a bonus.
Auto-X Fil
12-07-15, 19:54
More info. Longest shot right now would be about 300m. I currently live in Alaska, so I can't order ammo. Anything other than run of the mill 193 or 855, PMC, etc isn't available, so I will likely be handloading.
Obviously a heavy profile would maintain accuracy through sustained fire better vs a light/pencil, but would there be a noticeable difference in say a medium vs heavy?
What about fluting? I'm reading fluting is mostly snake oil and only good for looks.
I trend towards more even contours. All the cutouts in the mil-spec barrels are just silly for these uses. The SOCOM is the only one on your list that's like that - all the others are nice profiles.
Fluting removes a little weight. That's it. If the weight loss is critical to you, factor it in. In general, a fluted barrel will perform essentially identically to an un-fluted barrel of the same profile. Theoretically they should be worse worse, but it's a small amount of stiffness and mass lost, and practically it doesn't seem to hurt unless it's done poorly, leaving stress in the barrel.
The Faxon barrels are a little more battle-ready, with roomy 5.56 chamber and QPQ finish.
http://faxonfirearms.com/16-heavy-fluted-5-56-nato-mid-length-416-r-stainless-steel-qpq/
The BA is a Wylde chamber and more match-type, but a lighter profile. Kind of an odd combo, but I bet it shoots. No personal experience here, sorry.
http://ballisticadvantage.com/16-inch-223-hanson-625-mid-ss-premium-barrel.html
I think if you want a lighter gun and more reliable (in theory, anyway) gun, sort of SHTF ready, the Faxon wins over the BA in my mind. If it's just pure accuracy you want...
The Rock-Creek 5R Ranier is a proper match-grade barrel. If you're thinking about slow-fire, tiny groups, that barrel and tighter Wylde chamber would give you the best accuracy of the three. It's also the heaviest. If this is going to be a tack-driver, that $50 gets you a lot more barrel.
http://www.rainierarms.com/rainier-arms-223-wylde-barrel-16-rock-creek-blank
Hope that helps.
Cold is a non-issue, I'm a Southerner, I don't go out when its below 0 unless I have to.
I could be mistaken, but I thought I saw a stainless socom and heavy fluted bbl on your site a few days ago, now I'm only seeing the QPQ finished bbl's. Is this because the others are just out of stock?
What real world accuracy can I expect out of those 2 bbl's?
FaxonNathan
12-08-15, 09:09
Cold is a non-issue, I'm a Southerner, I don't go out when its below 0 unless I have to.
I could be mistaken, but I thought I saw a stainless socom and heavy fluted bbl on your site a few days ago, now I'm only seeing the QPQ finished bbl's. Is this because the others are just out of stock?
What real world accuracy can I expect out of those 2 bbl's?
Yes, our 5.56 stainless barrels can be found here: http://faxonfirearms.com/barrels/ar-15/5-56-nato-223-remington/416-r-stainless/
Not to be coy, but we do not formally state accuracy due to the myriad of factors that go into it that we cannot measure. What we do state is the bore is held to an excellent finish and that the concentricity is always .0002" or better. This is mechanically capable of fantastic accuracy.
Accuracy, while a large majority stems from the barrel, is the ultimate result of a system. As such, the headspacing, receiver, optics, trigger, and the shooter all come into play. Any one of those can take a "guaranteed sub-MOA" barrel and make it barely hit a the broadside of a barn at distance.
As such, we only guarantee what we can measure, including your satisfaction. If you're not, get ahold of me and we'll make it right!
All barrels were free-floated during testing.
https://app.box.com/shared/static/zy0a61s0qrl0aui5rtk1bfctrg4fqg05.jpg
....
Accuracy, while a large majority stems from the barrel, is the ultimate result of a system. As such, the headspacing, receiver, optics, trigger, and the shooterall come into play. Any one of those can take a "guaranteed sub-MOA" barrel and make it barely hit a the broadside of a barn at distance.
True ... but I think you forgot :confused: the AMMO being used and along w/ the shooter, I think those 2 elements are the biggest factors once one has a decent AR ...
FWIW I have ran several BA barrels
Good stuff.
The Hanson profile is nice for 3 gun bring light and I have ran the 14.5 and 16 out to 500 with XM193
I have ran both with a can.
Though I run light ones.
Crux Nemesis at 9 oz
Having said that.. If primarily from a bench I would go SPR 18"
Sent from my LG-D850 using Tapatalk
FaxonNathan
12-09-15, 10:36
True ... but I think you forgot :confused: the AMMO being used and along w/ the shooter, I think those 2 elements are the biggest factors once one has a decent AR ...
We did forget to list it. Thank you!
We see quite often that someone buys a "guaranteed accuracy" barrel and returns it as they cannot physically shoot that group themselves.
Don't need a guarantee, just looking for a ballpark average.
FaxonNathan
12-10-15, 08:13
Don't need a guarantee, just looking for a ballpark average.
Somewhere between home plate (one hole) to left field, but much, much closer to home.
;)
What we do state is the bore is held to an excellent finish . . .
Since you still haven’t posted any bore-scope views of the interiors of your barrels as has been previously requested, what exactly is your definition of “excellent finish”?
This is mechanically capable of fantastic accuracy.
Since you still haven’t posted any pics of groups fired from your barrels as has been previously requested, what exactly is your definition of “fantastic accuracy”?
...
FaxonNathan
12-10-15, 20:03
Since you still haven’t posted any bore-scope views of the interiors of your barrels as has been previously requested, what exactly is your definition “excellent finish”?
Since you still haven’t posted any pics of groups fired from your barrels as has been previously requested, what exactly is your definition of “fantastic accuracy”?
...
Rather than post something we did ourselves (which anyone would claim we were simply taking the best groups), below are targets sent to us by one of our OEM partners, Robar. There are the first three shots through a barrel, cold-bore, that is included with any gun they send out. Robar claims an MOA guarantee off our barrels and we have never had one returned from them for not meeting that requirement. *Note the grids are 1/2" squares.
We support and encourage OEMs who do this, as they are capable of controlling for the very things we say we cannot when selling a barrel by itself. They control the flange to receiver fit, headspace, trigger, optics, etc.
We're true gun-guys and engineers at Faxon. As such, we don't want to claim something we cannot verify and test without controlling for variables.
http://i1014.photobucket.com/albums/af268/NSSchueth/Robar2.jpg (http://s1014.photobucket.com/user/NSSchueth/media/Robar2.jpg.html)
http://i1014.photobucket.com/albums/af268/NSSchueth/Robar5.jpg (http://s1014.photobucket.com/user/NSSchueth/media/Robar5.jpg.html)
http://i1014.photobucket.com/albums/af268/NSSchueth/Robar3.jpg (http://s1014.photobucket.com/user/NSSchueth/media/Robar3.jpg.html)
http://i1014.photobucket.com/albums/af268/NSSchueth/Robar%201.jpg (http://s1014.photobucket.com/user/NSSchueth/media/Robar%201.jpg.html)
http://i1014.photobucket.com/albums/af268/NSSchueth/Robar4.jpg (http://s1014.photobucket.com/user/NSSchueth/media/Robar4.jpg.html)
On the bore-scope, forgive us as we have not seen requests to do so. In that respect, "excellent finish" is defined as free of mechanical defects that will gouge, disturb, or otherwise adversely effect accuracy. Meaning, there are no burrs, messed-up rifling, etc. Minor tooling marks are normal, as we do not hand-lap the barrels (though do offer the capability to OEMs).
We can post up photos, but to anyone not understanding exactly what they are looking at, the bore will look far different than what it performs (as most people expect a gleaming mirror finish, which is not the case in most barrels). The nitrocarburizing process leaves a bore splotchy and often the black oxide finish exacerbates any shadows. Minor tool marks, which are smaller than a millionth, will look devastating under the magnification, etc.
Mrgunsngear
12-27-15, 12:12
Assuming you want to maintain a good zero without groups opening significantly during spirited shooting, below is a good rule of thumb for choosing a profile:
1. 15 rounds or less: Pencil
2. 60-90 rounds: Gov't / Hybrid profiles (like our Gunners)
3. Any more: Medium & Heavies
We would make the blanket statement that people often buy "too much barrel" for their needs, often going heavier than they really require. Most people only care about their first shots and magazines and after that point, its a moot point.
So, if we may be so bold as to make a recommendation on profile and the above assumptions, the Flame may be a solid option, given its medium-fluted barrel, stainless, etc.
However, we would also caution against stainless in extreme cold environments. Even 416-R, which is what we and the other manufacturers use is typically only rated to -40F. Just know what you are getting ahead of time.
I'd generally agree with that. This test may be of interest to some folks in this thread.
I'm not the shooter Molon is but as you'll see below the pencil barrel can shoot pretty decently in a rest with a decent trigger as well:
http://www.youtube.com/watch?v=jnDsNTi4nmM
This test may be of interest to some folks in this thread.
http://www.youtube.com/watch?v=jnDsNTi4nmM
Nice work!
...
Ok, I'm finally ready to buy the bbl, but I actually prefer the matte stainless finish, and I'm only seeing the darker QPQ on the site. Are the matte bbl's OOS?
Edit: this message is directed at Nathan, just to clarify.
FaxonNathan
12-29-15, 09:05
Ok, I'm finally ready to buy the bbl, but I actually prefer the matte stainless finish, and I'm only seeing the darker QPQ on the site. Are the matte bbl's OOS?
Edit: this message is directed at Nathan, just to clarify.
Assuming you are asking us, we have opted to discontinue the matte finished barrels.
Simply put, stainless used for barrel manufacturing is not rust-proof and customers were complaining about corrosion when they left their rifles in wet conditions. Given the positive response to the QPQ finish on stainless, we kept the profiles, just adding the finish.
https://www.youtube.com/watch?v=cSMwCXO2gbU
https://www.youtube.com/watch?v=h407yVskVeM
some interesting discussion on what makes rigidity
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