Changing uppers from rifle to carbine, do I need to change buffers?

[wnycollector]

Ar newbie here. I picked up my first AR about a month ago. The lower is a RRA national match with 2 stage trigger and the upper is a del-ton 20" government profile. I have an acquaintance that is strapped for cash and is looking to sell a 16" carbine upper cheap. If I pick it up, will I have to change the the buffer (or spring) to account for the increased gas pressure of the carbine?

 

[Logan5]

No- If the carbine upper is still .223/5.56 you're fine. (If it were a 9mm or something you'd need a different buffer, spring, and spacer to run with a rifle length buffer tube.)

 

[Mags]

No rifle buffers are for A2 buttstocks since they are longer. Carbine buffers are for carbine stock extension tubes. So the buffer has to do with your caliber and your lower extension tube. To make things more crazy barrels 14.5 inches or shorter work well with H-H2 wighted buffers.

 

[Jeremy2171]

Depends you just need to try it..sometimes you can get away with a carbine upper on a rifle lower..sometimes you need to put a carbine buffer in the rifle lower. Just need to see.....

 

[Zak Smith]

Depends you just need to try it..sometimes you can get away with a carbine upper on a rifle lower..sometimes you need to put a carbine buffer in the rifle lower. Just need to see.....

ABSOLUTELY FALSE.

Putting a carbine buffer in a rifle receiver extension ("buffer tube") and firing the rifle will cause damage. The shorter carbine buffer will not "bottom out" properly in the rifle receiver extension tube.

There is no "need" for a heavier buffer weight or spring weight when changing the upper; however, it can mask other problems with the rifle system (usually mags).