16" barrel length w/ carbine gas
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cubrock
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As it has been explained to me, the carbine gas length is optimized for a 14.5” barrel, so it overgasses the action with a 16” barrel. Thus, the marginal increase in felt recoil and an increase in parts wear. For most of us, this is arguing about how many angels can dance on the head of a pin. For those who run thousands of rounds a year through their ARs, it might matter. Amongst that latter group, there is still debate.
I like a mid length gas system with a 16” barrel, but I own both types.
I like a mid length gas system with a 16” barrel, but I own both types.
OP
Torn and Frayed
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Guess I won’t throw the 6920 in the burn pile. Any recs on aan 11.5 upper? Seems kac and lmt are unobtainable so bcm is the standard. Also if you were going to double stamp it would you use gov or lightweight barrel profile?
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The LMT's are out there, but $$$.
No bcg either. I'm an LMT fan, but it does wreck the wallet.
I'm extremely happy with my 11.5" Barnes. Maybe worth a call to them to get a stock update. I changed the charging handle and replaced the stock with a SBA3. Runs great and made in NC.
BPM – BPM – Barnes Precision Machine
www.usamade-ar15parts.com
OP
Torn and Frayed
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My fil has a Barnes. It is nice, I should give them a callThe LMT's are out there, but $$$.
No bcg either. I'm an LMT fan, but it does wreck the wallet.
I'm extremely happy with my 11.5" Barnes. Maybe worth a call to them to get a stock update. I changed the charging handle and replaced the stock with a SBA3. Runs great and made in NC.
BPM – BPM – Barnes Precision Machine
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I can pm some pictures of my Barnes if you'd like. I have a 16" too, looks identical but short in 11.5". Some of the older Barnes have a different handguard than the recent ones, not sure which one your FIL has.
The pistol brace that came with is a boat anchor...I changed that immediately.
RedneckFur
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I've got several in each configuration. 16" carbine gassers do tend to overgass a little, and can have a stronger recoil impulse, and in some cases may throw brass backwards. A heavier buffer helps to take care of that. 16" carbine gassers are just as reliable and accurate as any other AR.
16" middy gassers tend to be softer shooting. Its a noticeable difference in recoil. Aside from that, I don't see any other differences in accuracy, wear, etc.
In my experience, piston AR's are the softest shooting of all, but that's a whole 'nother can of worms.
My Ruger SR556 feels like shooting a very loud BB gun.
16" middy gassers tend to be softer shooting. Its a noticeable difference in recoil. Aside from that, I don't see any other differences in accuracy, wear, etc.
In my experience, piston AR's are the softest shooting of all, but that's a whole 'nother can of worms.
My Ruger SR556 feels like shooting a very loud BB gun.
That info is myth.
The CAR-15 came with 10.5 and 11.5" barrels. In the 60's the gas block was a front sight post.
Reverse engineering the process, a Front sight post is 2.25" wide, plus the barrel threading on a .223/5.56 is 1/2x28. So adding that length = 1/4" of clearance you have .25+.5+2.25= 3.25" of barrel length. As we know, 5.56mm is a BLASTER in short barrel configurations. So if you go 10.5" off the bolt face of the barrel and subtract 3.25" you get a 7.25" gas system.
Fast forward to 1992 and FN was eating up the .gov military rifle contracts. Colt had to come up with something unique. So they did three patent's to separate the M4 from the Ar-15.
the 14.5" barrel length reality.
14.5" was chosen due to one and ONLY one reason.
1. The firearm was being sold to the U.S. Army, they needed the M9 Bayonet to fit. Or the school of Infantry would not approve the carbine.
2. If you take the 10.5" CAR-15 Barrel and Gas system, lock in a M9 Bayonet, to a FSP, the bayonet muzzle loop times out on the A2 flashhider at 14" from the bolt face.
That's it. No super special barrel length, no great ballistics, nope. A Infantry rifle needs to support a bayonet. Period.
cubrock
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That is a pretty persistent myth amongst a bunch of people, including some whose weapons knowledge I have found to be excellent across the board. Thanks for the clarification. Great info.
What is your opinion of mid-length gas systems?
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Midgas.
I was the first ever in the industry to go to market with a 11.75" midgas on the LVOA-S in 2011. We built a hell of a platform that is the softest shooting system at that time " 2011-2016 AR platform".
I think a mid DI gas system works, so do many other systems. I always go back to the M1 Grand. If that piston system worked with 30.06 and damn near no dwell, then almost any system can work too.
I love a AR-180 piston system and think a hybrid of AR-180 and the HK G3 roller delayed is the best of all worlds, do to how each system would keep the firearm more clean.
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