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.