Which buffer for full-length gas system?

[Dapimpspimp]

Hey guys I know this has probably been covered before. I tried the search function and found a whole bunch of stuff on mid-length systems but not rifle length systems.

So here goes. I have a co-worker with a rifle length gas system Colt A2 with a fixed stock. I'm helping him covert the stock over to a m4 collapsible stock. Should I use a carbine or H buffer? This stock is going on a patrol rifle. Are there any problems that I am going to run into?

Thanks.

[PRGGodfather]

For this circumstance, the standard carbine buffer should be fine, and for a Colt A2 20" bbl, I'd bet both will work acceptably. Buffer weight selection becomes more critical in the carbine-length gas systems.

As the gas system gets shorter, the internal pressure and heat increases, which will shorten the life of the internal components, but this by itself does not automatically mean reduced reliability.

Thus, in a carbine length system, the internal pressure increase also results in a faster cycle rate, which can create some reliability problems, because the timing of extraction and ejection can be affected.

Since the rifle length gas system has the lowest pressure already, I suspect either weight should be fine, and I have seen reliable function with both weights in rifle-length gas systems.

If reliability for 5.56 Patrol Rifle is the question, this the general rule:

Full-length gas tube: Standard
Mid-length gas tube: Standard
Carbine-length gas tube: H Buffer (or heavier for an SBR)

Yet, I have little doubt several members have experienced various levels of success with all kinds of recipes.

Pistol caliber SBR's usually prefer H2 or H3 buffers, based on what I have learned from this forum -- as I personally have little experience with them, and have even less use for them as Patrol Rifles.

I run standard carbine buffers in my middies and H buffers in my carbine-lengths -- and all have survived several high-round-count courses with no timing problems. I prefer the middies, FWIW -- less noisy, and seem to recoil less than the shorties.

I wouldn't expect any problems with either selection, but YMMV.

Please be sure to torque and stake the castle nut properly, as that is the more significant problem users can induce with this planned conversion. Having the castle nut loosen during a firefight would be a bad thing.

[Dapimpspimp]

PRG,

Thanks for the reply..your advice is really appreciated.