What buffer and spring for A5 tube?

[JohnS]

Hi, I'm a newbie. Have worked and put together many AR 15's but a 308 AR is new to me. Got a 308 dpms style upper from Bear Creek. 18" with mid length gas system.

Ordered a BCMGUNFIGHTER STOCK MOD 1- SOPMOD STOCK, and BCM Intermediate Receiver Extension (A5 Buffer Tube). Just looking for advice on a buffer, and buffer spring. I've check on this site, and others, but recommendations on a buffer and spring are all over the place. Any recommendations from members would be welcome!

Thanks,

John S

[Armed Eye Doc]

Welcome to the forum.  Look at this thread for some information.

https://forum.308ar.com/topic/21706-buffer-spring-advise/?tab=comments#comment-338701

[Armed Eye Doc]

The tl/dr version of that thread:

The A5 receiver extension the same size as the Armalite carbine receiver extension  You will need a 3.25 inch buffer that weighs about 5.4 oz to reliably function your rifle.  You can get the Armalite carbine buffer or an Armalite AR10 compatible buffer from www.heavybuffers.com.  The best choices for spring will be either the Armalite AR10 spring (it uses the same spring for rifle or carbine) or the Sprinco red spring. 

The carbine recoil system as a whole is completely interchangeable between DPMS and Armalite based 308ARs.  You just can't mix parts between the two.  

[JohnS]

Thanks for the info!

[98Z5V]

11 hours ago, JohnS said:

 BCM Intermediate Receiver Extension (A5 Buffer Tube). Just looking for advice on a buffer, and buffer spring.

ONLY way to go on that is a regular old AR15 Carbine buffer (3.250" long) in the H3 weight (5.4oz).  Those are all over the place, so just make sure its the AR15 Carbine buffer and H3 weighted.  Spring is easy.  Armalite EA1095 spring. Done.

Edited August 14, 2021 by 98Z5V