I can’t find a specification anywhere, so I figured I’d ask, does anyone know the proper weight of a semi-auto and full-auto bolt carrier group assembly?
I weighted one of my Bushmaster semi-auto bcg on a postal scale (hard to read and unknown accuracy) and it’s around 10.25 ounces, my Colt M16 bcg is around 11.5 ounces. I read somewhere in a thread the M16 bcg is 1.4 ounces heavier. Anyone know the actual specs (trying to ascertain an issue with H, H2 or H3 buffers vs. total bolt/recoiling weight)?
I wouldn’t call it ‘heavier’, I’d call it standard. It’s like calling a Beretta M9/92 standard 15 round mag a ‘hi-cap’, it’s not a ‘hi-cap’ it’s simply standard. A 10 round Beretta M9/92 mag is however ‘low-cap’.
Using a lighter than M16 carrier in a CAR length gas length AR is like putting 14" wheels on a 2001 Mustang GT, it was designed around 17" wheels…why would you 2nd guess the Ford engineers and go smaller?
The M16/M4 was designed using a full weight M16 carrier. M4s have had upgrades to fix the very fast cyclic rate with an M16 carrier…things like upgraded extractor springs, Crane o-rings, heavier buffers etc.
Using a lighter carrier will only circumvent some of these upgrades and/or have the problems return with ARs with carbine length gas systems. There’s no reason to use a lighter than M16 carrier when using M16 carriers is completely legal and easy to do.
I only use a lighter (unshrouded 1/2 Colt AR15 carrier) carrier on my 3gun rifle, it’s a midlength and runs 100%. When I rebarrel it with an 18" rifle gas it’ll get a JP LMOS carrier and an adjustable gas block.
This is precisely what I was looking for / why I was asking. So the M4 gas system is designed around a carrier weight of roughly 9.46 ounces (assuming CMT M16 carrier is built to the TDP), correct?
Ergo the necessity of adding 0.87 ounces in mass to the buffer (H buffer vs. standard CAR buffer) which is roughly the difference in mass between the M16 vs. AR-15 carrier (though that would be a different total reciprocating mass…but adding 1.5" to the barrel also changes things around a bit). Am I correct in this assertion?
Right! I always use them if I’m building my own. My point was that TOS was always spouting that the 16 carrier was critical because it slowed the bolt group movement down. The weight difference is much less significant than the weight differences in buffer choices.
I agree with you that the emasculated carrier is non standard, and I find it philisophically repulsive!
