Ordered a 20" rifle length upper

**TheNegativeOne** · 05-06-16, 11:33

So I ordered a 20" rifle length upper thinking I would mate it with a lower I had sitting around for a while but now that Im thinking about it, doesnt that upper need a different buffer tube? Or is it just a different buffer?

**VIP3R 237** · 05-06-16, 11:46

20" Rifle gas uppers run best with a rifle buffer and spring. If you want to keep an adjustable stock option the Vltor A5 system works very well.

**TheNegativeOne** · 05-06-16, 12:10

Well the a5 is out of stock everywhere I looked so, new lower it is. Hell Im gonna put a carry handle on it and go old school.

**M90A1** · 05-06-16, 13:39

It'll work with a standard carbine stock and buffer tube. You might have to play with different buffer weights and different springs, but the basic setup will work.

**jhr1986** · 05-06-16, 13:47

http://www.bravocompanyusa.com/BCM-I...ediate-shk.htm

New lower is good too though.

**ColtSeavers** · 05-06-16, 21:06

There is no rule, mandate or doctrine that states what gas sytem length must be used with what reveiver extension/recoil system length.

Want to use a 14.5" carbine gas length upper with a rifle receiver extension/recoil system? Have at it.

Want to use a 20" rifle gas length upper with a carbine receiver extension/recoil system? Knock yourself out.

The only rule, mandate and/or doctrine that must be followed is to not mix and match receiver extensions with other recoil sytems' buffers and/or springs.

You want to use a carbine receiver extension/recoil system? Then you must use a carbine buffer and spring.

I believe the A5 system uses rifle recoil springs, however it still uses it's own buffers and receivers