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p246
04-07-2015, 03:51
I've emailed AA, waiting for reply. If one puts a rifle length conversion on can they use a carbine length buffer tube, buffer and spring.

I'm looking at a friends new build that is short stroking about 20% of the time with 55 grain fmj and 10% of the time with 64 grain stuff. It will fire and eject but when it fails it does not pick up the next round. When checking with no ammo in the magazine it does not lock open at the same percentage rate. It is ejecting about five feet at the 3 oclock.

Twice (one 55 grain Armscore, one 64 grain Winchester Ranger) it picked the round up started to lock up but bound up. I had to stomp on charging handle to clear it. Reloaded round and it went bang. No bad marks on brass.


I opened it up and all looks installed right (headspace good). I can see no binding or suspect wear patterns but were not at 100 round count yet.

Parts

Wilson heavy match barrel (18 inch)
Adams Arms Rifle Piston Kit
Adams low mass one piece carrier
zero fail bolt
Vlotor Upper
Spikes Tactical lower parts kit
Spikes Tactical buffer tube/spring heavy buffer
Samsom fore end (on Adams list of acceptable fore ends)

with Spikes heavy buffer it short stroked almost all the time. I put a 3.5 ounce carbine buffer in it for the results listed at top.

So before I dive deeper I'd like to know if the Rifle Piston can be used with the carbine buffer. AA website does not say that I can find. Any help appreciated.

Adams Arms
04-08-2015, 07:17
P246,

I apologize, but i don't see an email from you in the sales inbox(maybe it went to support), but was notified from Google alerts of your question.
You may use any buffer and spring combo with the Adams Arms piston system. It sounds like your heading in the right direction as far as tuning.
When we build our COR rifle, we tune it with a low mass carrier, A Rifle fixed stock and tube, a Rifle buffer, with a carbine spring. We have had great results with that combination as that is what our 3 gun shooters use.
With the rifle length piston system a heavy buffer like your spikes is almost guaranteed to short stroke.

If you need additional assistance, shoot me over an email at sales@adamsarms.net Attn: Brian and I'll get you squared away.

Brian
Adams Arms

p246
04-08-2015, 02:32
Thanks for the reply, yes I sent it to CS, I want to try a different buffer tube, if that does not work I'll get back to you.

p246
04-09-2015, 02:34
Gun is fixed and running like a top. In original post I said the buffer was changed to a 3.5 oz. one I had. I used some cheap food scales to weigh it originally. On my better scales it weighed just over 3 0z., took one weight out and it weighed 2.25 oz. Once back together I put 100 rds of 55 grain Armscore on regular gas setting. Ran it all with ejections at 3 o'clock at about 5 feet. With 75 grain Hornady on low gas setting it ran with same ejection pattern.