Just got a brand new bushmaster xm15. Have metal mags that work perfectly. However, just bought a black polymer promag that worked fine at first but now won't even chamber a round. My bolt keeps getting stuck on the mag and I have to pull it out and the bolt slams forward. Again no other problems with other mags. AR is in perfect condition, took it apart, cleaned and everything.
Any thoughts? Should I file down the back a little bit? It seems the bolt is catching on the back of the mag.
EDIT: the round I was testing just smashed into the space below the chamber. I've figured out that the bolt is fine. It is smooth with no round in. But with a round it jams?
Any thoughts? Should I file down the back a little bit? It seems the bolt is catching on the back of the mag.
EDIT: the round I was testing just smashed into the space below the chamber. I've figured out that the bolt is fine. It is smooth with no round in. But with a round it jams?