Bought this from a buddy at the range yesterday. He warned me about hollow-point problems, but I did not know that almost every new Winchester hp round would jam at an upwards angle, and sometimes send a spark from the bolt. With ten rounds of Federal lead bullets, the freq. of stovebolts is about the same with both ammo types. Maybe a spring should first be ordered, to avoid an extra 15-mile trip to the gun smith? Have no idea what the problem could be.