UMP / USC Bolt Carrier Groups

Michaels Machines HK UMP .45 Semi-Auto Bolt Group - Complete MM’s UMP Tungsten filled UMP .45 bolt carrier complete. Heat treated, parkarized and polished for the best look and function possible, as an added bonus it now includes German HK...

HK UMP 9mm Conversion Kit - US-Made UMP/USC conversion kit will convert existing USC-UMP conversions to 9mm. This is a simple drop-in conversion for those who have already done the USC-UMP conversion. The conversion parts are drop-in, with the total swap...

HK UMP 40 Caliber Conversion Kit With this UMP Conversion kit, UMP .45 sub guns can be converted to .40 caliber. Machined bolt carriers are available for USC/UMP conversion sub guns. This is a simple drop-in conversion. The time required to change...

Heckler and Koch HK UMP40 Bolt Group - Semi-Auto - 40 S&W - USED ONLY 3 UNITS AVAILABLE - VARYING CONDITION SHOWN - SOLD INDIVIDUALLY Complete factory HK bolt group for semi-automatic UMP firearms chambered in .40 S&W. Intended for replacement,...