PDA

View Full Version : Buffer / Spring Weights - gas/barrel length.


speeddreamz
05-08-2011, 10:47 AM
I searched already under "buffer weight" perhaps thats not the right term.

I'm curious about different barrel lengths, gas systems and how the buffer and buffer spring work in conjunction.

From my understanding, a shorter gas system, i.e. an pistol length or Carbine length gas system would require a heavier buffer. A mid length would use a lighter buffer and spring?

I used to have a mid length 16" and now I have a carbine length 14.5, used same lower setup with same stock, I haven't shot them side by side but I'm guessing there could be some added recoil with the carbine. Could I negate this by purchasing a BCM h2 or h3 buffer? What about the spring?

I'm guessing using an h2 or h3 buffer with a rifle length gas system would cause it to function unreliably but reduce recoil when it cycled.

On another subject, I am building an AR-10, so it needs a far heavier buffer correct?

pacrimguru
05-08-2011, 10:54 AM
from my experience, going from 16" to 14.5" doesn't create that big of a difference recoil wise. you can go with a heavier buffer to help smooth things out and make it easier on your internal components though. i've used an H1 in a 14.5" and tried the H2. in the end i went with the H1 because i didn't want to risk having problems running different kinds of ammo. i did not swap out the standard spring in any case.

i've tried an H1 in a rifle length system and it seems to work just fine. in the end, i went with the regular buffer anyway because it's smooth enough shooting as it is.

missiontrails
05-08-2011, 11:01 AM
My last CMMG carbine, 14.5" barrel..... I ran a Colt 9mm buffer, 5.2oz (I believe) and it was perfect for that rifle. Aside from gas system "length", there are variances in gas port size. Some can be more or less than .064"...... My CMMG was "overgased", which meant slightly larger hole, which also meant that it would cycle even weak .223 ammo. My brothers Colt 6940 seems to be gased to spec, or slightly under, because it cycles Russian .223 poorly, but 5.56 perfectly. He uses a normal 3oz carbine buffer with that.

I ran the Colt buffer at the bottom of this page: http://pkfirearms.com/Stock_Parts__Accessories/12/c

motorwerks
05-08-2011, 11:42 AM
I run a normal non-h buffer in my 14.5 and its fine. It doesn't have much more muzzle flip then my 16 with a Tubb spring and Spikes tungsten bugger.

speeddreamz
05-08-2011, 1:38 PM
My last CMMG carbine, 14.5" barrel..... I ran a Colt 9mm buffer, 5.2oz (I believe) and it was perfect for that rifle. Aside from gas system "length", there are variances in gas port size. Some can be more or less than .064"...... My CMMG was "overgased", which meant slightly larger hole, which also meant that it would cycle even weak .223 ammo. My brothers Colt 6940 seems to be gased to spec, or slightly under, because it cycles Russian .223 poorly, but 5.56 perfectly. He uses a normal 3oz carbine buffer with that.

I ran the Colt buffer at the bottom of this page: http://pkfirearms.com/Stock_Parts__Accessories/12/c

Pretty much agree.

migz
05-08-2011, 3:00 PM
I have a relevant issue with my Daniel Defense carbine upper. I'm using a carbine buffer and spring, and it won't cycle .223 ammo. 5.56 ammo cycles just fine. would this be considered normal?

speeddreamz
05-08-2011, 3:18 PM
I have a relevant issue with my Daniel Defense carbine upper. I'm using a carbine buffer and spring, and it won't cycle .223 ammo. 5.56 ammo cycles just fine. would this be considered normal?

I wouldn't say it isn't. What kind of ammo are you using?

migz
05-08-2011, 3:24 PM
pmc bronze, centurion .223. Neither will cycle. PMC XTAC, and m855 cycle without issues