having problems with a particular mosin, of course the one that shoots the best. whenever i use the mag and i'm shooting, my rim gets jammed in the point that sticks out that the bullet is supposed to slide under( hard to explain, i'll use technical terms like doodad and thingy). this happens at least once every 5-6 rounds. no rhyme or reason to it, not the first round or the last round, just random rounds. for some reason its only when i shoot, i can cycle it all day in my living room with no problems. any help please, i have been shooting this rifle weekly just loading one round at a time for the last 2 yrs. i figure i should fix it now. heres some pics to explain........