Today I (tried) to go shooting after installing a set of JP springs in my 15-22. It only struck hard enough to shoot about 7 rounds. It set off one round, failed one, set one off, failed, then it shot for 5-6 in a row. Then, nothing. Everything in my gun is clean and lightly oiled, and last time it shot great. So this leaves me to think that the hammer spring was too light. Just comparing the hit up against my thumb, the stocker does hit a lot harder, so I would think that resolved it, butI could be wrong, and haven't tested it since going back to the stock, so I was wondering if anyone else had this issue.