Thanks GunFun FOR THE HEADS UP ON 922R compliance.I have purchaced and installed a Phoenix Technology kicklite buttstock with pistol grip,Phoenix Tech three rail forearm .Also an American made puck Tapco I think.And I also put and adjustable breached type choke on as well,also American made.This is probably the funnest weapon I have.When I pull it out the the case at the range it draws a lot of attention.Pop in a 20 round drum and bump fire till empty really gains attention.Back to the SGM mag thing.Holding the mag in your hand facing forward the half moon cutout where bolt grabs the next roun