Jack19
Member
If I wanted to put a 9mm upper on my 5.56 lower, I understand I'll need, obviously, 9mm mags and a mag-well adapter.
Is that all? Do any of the internals on the lower need to be changed? And,
if so, how does that effect my ability to also shoot 5.56?
Is that all? Do any of the internals on the lower need to be changed? And,
if so, how does that effect my ability to also shoot 5.56?