UMP / USC Bolt Carrier Groups

HK UMP/USC (9mm) Semi Auto Bolt Carrier The semi-auto bolt group is needed for HK USC to HK UMP caliber conversions. The full-auto bolt carrier will not work in HK USC rifles.  Specifications: Tungsten Filled Heat Treated Parkerized &...

HK UMP 9mm - Full Auto Bolt - Stripped The full auto bolt carrier is for HK UMP rifles. The full-auto bolt carrier will not work in the HK USC conversion rifles. One of the finest aftermarket carriers you can buy. Features: Tungsten filled Heat...

Michaels Machines HK UMP .40 Semi-Auto Bolt Group - Complete MM’s UMP tungsten filled UMP .40 bolt carrier. Heat treated, parkarized and polished for the best look and function possible, as an added bonus it now includes German HK internals which...

HK German USC .45 Factory Semi Bolt - Incomplete HK German USC, Omega GS 45 caliber bolt carrier that is stripped. Just add the firing pin, firing pin spring, extractor and firing pin retaining pin for a complete bolt. Made in Germany.

HKP HK UMP 9mm Conversion Kit -Threaded 1/2x28 9mm UMP/USC conversion kit will convert existing USC-UMP conversions to 9mm. This is a simple drop-in conversion for those that have already done the USC-UMP conversion. The conversion parts are drop in with...