I bought a 50's Mossberg M42 from a friend of my in-laws over the summer for 50 bucks. Took it home and could only get it to fire 1 out of 5 rounds. It appears I'm getting light strikes on the rim. Anyone have any suggestions to get her back in firing condition? I didn't buy it to shoot it a lot, just for the historical factor but it would be nice to have it in firing condition.