Special 9 mm buffer and standard carbine spring will work. ATI actually makes a pretty nice adapter to use Glock magazines. Add an upper of your choice and you should be good to go. Make sure your trigger is PCC rated which means pistol caliber carbine.
I've looked at going this route but personally I would recommend dedicated lower.
The above recommendation is with the idea of the bolt carrier is included with the upper .
Last edited by ldholton; 12/14/21.
