Need Help Finding a Sub MOA 11.5 or 12.5 Barrel (Moved)

[MistWolf]

It just seems to me a 12.5" barrelled AR would be pretty difficult to shoot 1" groups with no matter what barrel was used.

There's no reason a 10.5/11.5/12.5 inch barrel can't be as precise as longer barrels.

[fledge]

Tell me how you do it and include pictures.

I was teasing, quoting a well known firearms instructor. As others have questioned, why would it it hard with a shorter barrel, in your opinion?

[MQ105]

I think sub-2” 10rd groups with Wolf Gold is darn good (from the Sionics barrel.) This barrel shoots LC M855 sub 2” and ADI 69 SMKs into 1.25”. All 10rd groups. That is quite good, in my experience, for any barrel.
Also check out Criterion. They have a run of 12.5” hybrid contour barrels that will be ready in a week. They are known to be very accurate and durable.

@mq105 - wow thanks for the groups. That is some valuable data.
I had an upper that absolutely hated 69gr and up. Looked like your groups on the MK318. Was sub moa on 55gr though. Supposedly 1/8 twist but I suspect it was closer to 1/9

Seems like the Sionics is a bit more picky in 11.5
The DD 10.5 seems to like the heavier rounds but does OK with 55gr too.

I am down to these barrels:
TriArc 12.5 (mid length) (unknown gas port) $260
Sionics RGP 11.5 (carbine) (.070 ?) $200
Daniel Defense 12.5 (carbine) (.0595 per Brownells which seems super small?) $275
Centurion Arms 12.5 LW (carbine) (.070?) $330
These are all around 1.4 lbs give or take .1lbs
but the Centurion Arms is lightest at 1lb 5.1oz which is about 2oz lighter.

But sub moa with 77gr is priority, then gas port though I will be using an SLR7 adjustable block

[HelloLarry]

There's no reason a 10.5/11.5/12.5 inch barrel can't be as precise as longer barrels.

Clamped in a machine rest, yes. From your hands, that is a little more problematic.

There are a couple reasons why a short barreled AR is harder to shoot than a long one, centering on weight. First off a 4lb trigger is over 70% the weight of a 5.5lb rifle, making it more sensitive to trigger technique then a 4lb trigger on a 10lb rifle. A variation in cheek pressure of 2lbs 12 oz is half the weight of that 5 1/2lb rifle compared to about 1/4 the weight of a 10lb rifle making the short rifle more sensitive to cheek pressure. Now think about shoulder pressure, grip pressure and pressure on the forearm - the effects are all magnified.

Those are some VERY good groups in the pictures, but there aren't any sub-MOA groups in those pictures from a barrel that I'd bet money would turn out sub-MOA from a machine rest. There's a reason accuracy competition favors heavy rifles.

I'm just asking a honest question - how do you wring the best accuracy from those little guns?

[MQ105]

No doubt, in a static, set-position type competition the advantage goes to a heavier gun. Considering only the barrel's intrinsic accuracy potential, shorter is better.
The purpose of shorter barrels/guns is maneuverability, concealability, relative ease of carry, etc. For me, the only reason I shoot my SBRs for accuracy is to determine the capability of the system (gun, ammo, optic), removing as much shooter influence as practicable. It allows me to have realistic expectations of the complete weapon system - gun, ammo, optic, conditions, shooter.
For example, is it realistic for me to expect 2 MOA 10rd groups @ 100m from a barricade if I can only just achieve that accuracy level while "benched?" Similarly, if I'm shooting 5 MOA groups from the prone, but my system is capable of 1 MOA "benched", then I know I'm not doing my part from the prone.

[HelloLarry]

Do the rules of your game require a sub-MOA carbine? Like shooting 1" targets at 100 yards?

I'm just kind of puzzled. For such a short, light rifle, I'd grab a chrome lined DD barrel and not worry about it as long as it could cut about 2 MOA.

We've been over something like this in Highpower and the conclusion is pretty much that there isn't 1 shooter in a 100 that can tell the difference between a 1 MOA gun and a 1/2 MOA gun. An engineer that goes by ChrisF did some math that is pretty convincing. I won a HP match the other day with a rifle that only shoots MOA on a good day. It's really a 1 1/2 to maybe 2 MOA gun.

But we still buy barrels that are good for 1/4 MOA even if none of us can shoot it!

[MistWolf]

Clamped in a machine rest, yes. From your hands, that is a little more problematic.

There are a couple reasons why a short barreled AR is harder to shoot than a long one, centering on weight. First off a 4lb trigger is over 70% the weight of a 5.5lb rifle, making it more sensitive to trigger technique then a 4lb trigger on a 10lb rifle. A variation in cheek pressure of 2lbs 12 oz is half the weight of that 5 1/2lb rifle compared to about 1/4 the weight of a 10lb rifle making the short rifle more sensitive to cheek pressure. Now think about shoulder pressure, grip pressure and pressure on the forearm - the effects are all magnified.

Those are some VERY good groups in the pictures, but there aren't any sub-MOA groups in those pictures from a barrel that I'd bet money would turn out sub-MOA from a machine rest. There's a reason accuracy competition favors heavy rifles.

I'm just asking a honest question - how do you wring the best accuracy from those little guns?

Your objections apply to rifles with different masses, not barrel lengths. The mechanics of shooting a shorter barreled rifle (or a rifle with less mass) are basically the same as shooting a longer barreled rifle (or a rifle with greater mass). Either way, the shooter has build good form and be consistent. Learn good shooting techniques and practice them.

Back in the late 80s, early 90s, pistols using rifle calibers became all the rage. The most common barrel lengths were 14 inches and shorter. Without buttstocks, shooters were getting well under 1 MOA groups out to 300 yards. If shooters back then could achieve groups that small without buttstocks or any kind of arm brace, shooters today can achieve good results with an SBR or arm brace equipped pistol.

Stop over thinking it and go shoot!

[308sako]

It just seems to me a 12.5" barrelled AR would be pretty difficult to shoot 1" groups with no matter what barrel was used.

Barrel length has absolutely nothing to do with precision. End of story!

[joeg26er]

"Also check out Criterion. They have a run of 12.5” hybrid contour barrels that will be ready in a week"
will these have 1/7twist? I've seen 12 and 12.5 Criterion that have 1/8 which I'd rather not do.

[everready73]

"Also check out Criterion. They have a run of 12.5” hybrid contour barrels that will be ready in a week"
will these have 1/7twist? I've seen 12 and 12.5 Criterion that have 1/8 which I'd rather not do.

Compass lake could probably do a 1/7 Criterion. Give them a call, they make fantastic barrels