I had a 14.5 carbine cut & threaded for a pistol build. The barrel is a DD LW & port size is .066. I've googled the optimum port size for an 11.5 barrel with port sizes from .071 to .096!
So what says the experts?
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I had a 14.5 carbine cut & threaded for a pistol build. The barrel is a DD LW & port size is .066. I've googled the optimum port size for an 11.5 barrel with port sizes from .071 to .096!
So what says the experts?
I believe BCM 11.5" barrels have a port size of 0.076. I'd shoot for that.
.076 would be a recommend size. That is used by at least a few well-known companies and works perfectly.
How in the Fudge does the LMT 10.5 run so good at .071"??? Even with an H3, the thing is still spunky and poppy as hell.
I prefer the smallest port size to get done what you want. A regular mil-spec chamber and similar rifling can handle 5.56 pressure ammo with a gas port much smaller than what's listed. Depends on what the OP wants to do? What ammo, action system, buffer weight, type of carrier, any suppressed use, etc. I don't run a .076" in any 11.5" that I port.
Pistol type AR's tend to be gassed harder than the rifles for general reliable function. I'm not a fan of AR pistols, but there is a market for them. Just depends on what the OP wants to do.
No suppressor. I'll try an H buffer first & go from there. Colt's are .081 for an 11.5 so I'm going to .078. I'm just building this as a range toy.
Don't do anything rash like wallowing out a perfectly good small port...
The easiest way to make an otherwise good AR unreliable is to overgas it and use a light buffer.
You want a reliable range toy, right?
Start small.
Go with .070 and an H2 buffer.
If by some miracle, that doesn't work, it can be bumped up a size or two.
But try it first and report back.
Figured I'd ask this here rather than starting a new thread.
INFO: I have a 11.5" BCM SBR. I'm waiting on a stamp for a can to come back. I would like to have this gun by very pleasant to shoot with the suppressor, as in tune the gas down for suppressed. I invision the gun being shot mostly suppressed with some unsuppressed. It has the Vltor A5 and the LMT enchanced carrier with a standard BCM bolt. I have the range of A5 buffers from 0 to A3, will getting a A4 at some point.
Question: Can anyone advise a insertalbe gas port (from Black River tactical) size that I could put in that would run and barley lock backon un-suppressed with the A0 buffer and suppressed with the A3 or A4 buffer? I would be doing this to avoid an adjustable gas block (for now pretend that a adjustable gas block is off the table). Basically wondering what the smallest port I could go with that will lock back unsuppressed with the A0 (which in my mind would cut out a lot of extra gas when running suppressed).
Thanks for any info.
I don't know what the Black River Tactical size would be but this info may be of some use.
Many .062" ported guns cut down to 11.5" with the LMT Enhanced carrier and A5 action systems use heavier than the A5H0 without a can. I know of a few .058" ported 11.5" guns that do as well. There's more variables, probably biggest is ammo, that comes into play.
They offer:
.055
.060
.063
.067
.070
I only shoot full power 5.56. Next question. If I could run a .063 or .060 gas port reliably unsuppressed would that make a noticable difference in the amount of gas and snappyness of the rifle when suppressed vs the stock .076"?
Thanks
Well, you can always send an email to info@
Gassing with suppressors is always difficult.
Different makes and models affect the gas drive differently.
The A5 and enhanced carrier are good choices to expand the envelope of performance.
.060" is a good starting point for mixed use, but YMMV.
Anyone know what the noveske 11.5 SS barrel is ported at?
.071-.076". Smaller end of the scale if suppressed, larger if not.
I don't know. But Pappabear has one in a Vltor VIS upper, and it is literally THE BEST AR15 I've ever shot. I think he's got an A5 buffer system, and that thing runs as smooth as a rifle. The thing piles up brass at 4 o'clock like a friggin machine.
I'd love to pull the thing apart and look at it, but it's so impressive that you just don't dare mess with it. I've got to shoot quite a few ARs over the years, and that gun is by far the best AR15 I've ever shot.