ORIGINAL: hillbillyhunter1
I'm not concerned about recoil, but is the .308 the same recoil-free weapon that the .223 is??
As I just stated on another post, I recently bought one (.223)and I honestly didn't know that different caliber uppers aren't interchangeable.I guess there must be conversion kits then??
Probably need a further clarification here. Cartridge OAL is essentially what determines "interchangeability" when it comes to the AR platform. There ARE some uppers that will marry up to your .223 lower:
9mm Para
.204 Ruger
6.8mm SPC
7.62x39mm
Of course, you'll need different uppers and bolt assemblies, as well as different/modified magazines.