308 AR Buffer Setup

[mic2377]

Hi All,

I am in the processing of building a DPMS-pattern 308 AR. Upper/lower are SI Defense, barrel is 18.5" Fulton Armory lightweight rifle gas, JP LMOS BCG (if I can get one in a reasonable time, if >6 months wait I'm going to find a standard mass setup!!), TRX-308 13.8" rail, Magpul CTR, and Miculek comp. No specific optics or trigger choice yet.

Now what is considered the ideal buffer setup for 3-gun 308 AR? There are several options that I know about:

1. Rifle extension tube/DPMS-308 specific rifle length buffer and spring. This is OUT as I want a collapsible stock.

2. Mil-spec AR-length extension tube/DPMS-308 specific shorty buffer (the one standard in DPMS 308 carbines, its TINY) and 308 spring.

3. VLTOR A5 buffer tube/standard AR buffer, AR-10 spring. This combination is certainly less proven.

Option #2 seems OK but I am not sure how heavily gassed the FA barrels are. This is the most "factory-like" option, and I am sure I could get the rifle to run particularly with adjustable gas. However, I feel the rifle would be under-buffered with that tiny little light buffer. I also feel the short, heavy spring is not ideal. I also understand I could go out and buy a Slash heavy buffer, but that is also $100+

Option #3 is a little more dicey. From my low level of google-fu, it seems that the VLTOR A5 tubes can be used with the AR-10 if used with a AR-10 buffer/spring. From my research, the AR-10 buffer is 3.25" vs a standard AR-15 buffer is 3.125" so it is conceivable that an AR-15 buffer would work as well, as long as extra .125" of bolt travel doesn't result in any unhappy contact at its rearmost extension. This would also allow me to dig into my well-stocked AR-15 buffer collection.

Also, before any yells at me, I understand that AR-10 and DPMS 308 patterns are not compatible. I have no idea how long the operating cycle bolt stroke is though, and I foresee that option #3 may very well be feasible.

Now too bad that I'll probably be waiting until summer for a BCG...

[carbon9]

I'm not sure about ideal but I am successfully running the JP LMOS .308 carrier with the JP SCS in a Magpul UBR stock and buffer tube(standard carbine length tube). You will want to run an adjustable gas block. YMMV.

[BigBamBoo]

I will 2nd the JP SCS in either a rifle or crabine setup. And also 2nd an adjustable gas block. Most large frame AR's are way over gassed (as well as AR-15's) and I will not have a AR (either large or small frame) that does not have a adjustable gas block.

Take care,Stan

[Larry White]

Call Benny Hill at Triangle Shooting Sports(361-241-1091) about his light carrier and buffer set up, with his comp and adj gas block makes a super soft and controable set up. Send your carrier and buffer, and get it in days, not weeks or years, days.---------Larry

[B_Ayers]

You might want to look @ a hydro buffer....it is a two stage design. Been running one in my DPMS LR-308 and love it. Benny Hill did the barrel work and running one of his rolling thunder comps. Right after I did this setup, My 13yr old daughter tried to take the gun from me to hunt with. She said it shot easier than my 30-30 or my ar15 @ the time. She shoots quarter sizes groups @ 100 yds with her Remington 770 in .270.

[CraigS.]

You might want to look @ a hydro buffer....it is a two stage design. Been running one in my DPMS LR-308 and love it. Benny Hill did the barrel work and running one of his rolling thunder comps. Right after I did this setup, My 13yr old daughter tried to take the gun from me to hunt with. She said it shot easier than my 30-30 or my ar15 @ the time. She shoots quarter sizes groups @ 100 yds with her Remington 770 in .270.

Are you refering to the enidine gas charged buffer ?

[mic2377]

I'm not going to get any whiz bang fancy buffer system that involves fluids or gases. A potential failure point that just doesn't need to be there. I will consider the JP SCS system. I have not yet decided what brand gas block will be going on, but it will be adjustable unless testing shows it won't be overgassed with a non-adjustable unit.

Too bad I'll be likely waiting on a bolt until June though...

[carbon9]

My barrel is a Fulton Armory, it was over gassed for the loads I am using. YMMV. My friend and I were amazed at the recoil reduction once we started tuning the adjustable gas. It made enough of a difference I will probably be revisiting adjustable gas blocks on my AR-15s again. I am using a clamp-on Syrac adjustable gas black, very easy to adjust. Personally, I would just spend the touch extra for an adjustable gas block from the start as it will probably save you money long term.

[mic2377]

Bolt arrived today - way ahead of what I expected. It looks like JP has turned up the wick on production! I also got a DPMS 308 buffer and spring along with it. I'm going to see how it runs with adjustable gas and the DPMS carbine buffer/spring and change if necessary. Still waiting on a barrel though...