Just replaced the springs, piston seal, used a T Robb's PTF one, and breach o ring in my LP 53, getting 440 fps using some old 177 wasps, what pellots are you guys using if you have a 53 that performs well, also have some original 177 marksman, but lose 30 fps with those and not as accurate. Doing the above raised the fps from 360 to 440. deerwarden.