Question about A5 buffer system

[dis_is_mike]

Hello all, I'm building a 6.5 Creed Ar10 specifically for NRL hunter. I have a Proof 24" barrel with a rifle +2" gas system. The buffer system is next and after some research I'm not sure which direction to go. Would the A5 buffer system with the rifle +2" gas system make for a longer "smoother" cycle? Or am I over thinking this and just go with a JP silent spring? I have minimal experience with the Ar10 platform. Thank you!

 

[rpol98]

I think you'll be fine.

I have a several 6.5CM AR large frames, one of them is a 26" Rainier Ultramatch, rifle+2. Another one is a 24" Criterion, rifle-gas. Another one is a 24" Faxon, rifle-gas. I have a few other 6.5CM uppers that haven't been dialed in yet, but that's beside the point.

I run all of these uppers on lowers with the AR-15 carbine buffer tube, AR-308 (shorty) 5.3oz buffer, and Slash's Heavy Buffer AR-10 308 carbine buffer spring ($17). Been running this for years, no problems. I use this combo for all my large-frame lowers, and interchange the lowers between all my uppers, 308 and 6.5CM. makes it easy if the lowers are "standardized", and the uppers are tuned to work with that combo. I got more built uppers than lowers.

SLR adjustable gas block on all my large-frame AR's. Well, except for the one 308 with the A2 FSB.

A lot of people swear up-and-down on a stack of bibles about the A5 buffer tube, so it must be good, allows you to use the AR-15 buffer, instead of the large-frame specific shorty buffer, 3/4" difference. meh, six-of-one, a half-dozen of the other. Po-tay-toe, po-tah-toe.

 

[ARlife4me]

proper gas port size conquers all no matter if it's a "+" system or not. i have an aero precision 22" standard length gas that's smooth and only using a standard weight buffer (non-h+ weights), standard weight spring and a non-adjustable gas block.................no issues on feeding/extracting or brass issues. a5's are ment for ar15's, but can be used in ar10's using an ar15 carbine buffer but can't recall which spring is used (don't have my notes at this time, but the spring needs to be 3/4" longer when compressed than an ar10 carbine spring)?

 

[ARlife4me]

carbine buffer lengths by frames

ar15 3.25"
ar10 2.5"

a5 buffer tube uses a 3.995" buffer, so spring will be different than both 10 & 15 carbine spring lengths for just in case you don't know.

i want too say the spring needed with the a5 tube and 3.25" buffer is an ar10 rifle spring. maybe someone will confirm.

 

[ARlife4me]

what makes an ar smoother to shoot is having less gas to move the bcg along with lighter moving parts. the a5 system is mainly for and designed for the 5.56 in a full to burst mode to tame the recoil to make it more reliable. the a5 uses around 3/4" longer tube and uses about a 4" buffer compared to the 3.25" carbine buffer. now i can't say that using lighter parts makes for less felt recoil as i have a 6.5prc using a 9.6oz (i believe that's what it weighs) rifle buffer on a +2 gas 22" barrel (w/ agb). felt recoil is very mild, but still needing to do more testing as it ejects around 2-2:30 (and no it's not overgassed). i'll reduce the buffer weight by 3oz and retest.

supposedly adding weight behind the bcg (buffer) will delay from unlocking that helps with lowering gas pressure? i haven't tested that yet.