no you cant do it. dont ask me why but ive asked the guy at my local gun shop because i was wanting to pick up a complete .308 upper and interchange on my lower and he said that i would have to get a lower made for a .308
i think your right is becuse the size of the round is bigger and requires a differnt size mag. but i could be wrong
i think your right is becuse the size of the round is bigger and requires a differnt size mag. but i could be wrong