5.56 upper work as a 7.62x39?

[chrisf]

I made a thread a couple months ago and didn't really get the answer. Will a 5.56 upper receiver work with my 7.62x39 build. Of course I'm going to use x39 barrel,bcg, etc. but is the upper receiver interchangeable??

[sharxbyte]

I'm going to go ahead and treat this as a serious post, because hey, we're all new to AR's at some point. On an AR-15 lower receiver, any AR-15 upper receiver will work. just make sure you use the proper magazines, and if you're going featureless, make sure all of our upper receivers are compliant.

[chrisf]

Thanks/thread

[Mr. Meeseeks]

http://www.calguns.net/calgunforum/showthread.php?t=580885

[FX-05 Xiuhcoatl]

the answer is YES