Does anyone keep a spare parts/springs kit for their USP? If so whats in it? I was told that nothing could hurt the HK barrels so what could break that would need replacement? Thanks.
The old school USP fireing pin has been known to break due to dry firing without snap caps. This was addressing in HK Armorer school.
I am not sure what year they changed out firing pins, but if you have the old style firing pin I would look into just changing it out to avoid the need for the spare part all together.
HKParts has photos of both the new and old style firing pins to see which one you have.