HDPS USC-to-UMP Conversion on HK USC .45 ACP Semi-Auto, 16 in Barrel, UMP Folding Stock, Made in Germany
This German-made Heckler & Koch USC has been professionally converted to UMP configuration by HDPS. The build retains the USC’s proven semi-automatic, direct blowback system and adds key UMP features: a folding UMP-pattern stock, UMP-style lower for double-stack .45 ACP magazines, a receiver-length top Picatinny rail, and a UMP-style handguard with accessory rails. It includes German proof and import markings and comes with one 25-round UMP-pattern magazine.
Condition
Overall Condition: Excellent condition, showing only faint signs of any prior use or handling.
Bore Condition: Excellent - Clean, mirror finish, no signs of wear.
Bore Rifling: Excellent Rifling - Sharp lands and grooves.
Specific Condition Notes: Functions properly in semi-automatic operation. External surfaces, controls, and stock are clean with only light evidence of handling.
What’s Included
- HDPS USC-to-UMP converted HK USC .45 ACP semi-automatic rifle
- 1x 25-round UMP-pattern .45 ACP polymer magazine with witness window; body marked 'Restricted Law Enforcement / Government Use Only'
Conversion was performed by HDPS, transforming the HK USC into UMP configuration while retaining its semi-automatic operation. The rifle features German proof/date markings, a "Made in Germany" receiver marking, and the Heckler & Koch Inc., Sterling VA import mark. The 16-inch, German proof-marked steel barrel anchors the build.
The UMP-pattern lower and magwell enable the use of double-stack .45 ACP magazines, complemented by a large paddle-style magazine release for intuitive reloads. An ambidextrous two-position selector with HK pictograms and a left-side charging handle round out the familiar HK control layout.
Furniture and mounting options mirror the UMP. A UMP-style handguard provides right and bottom accessory rails, and a receiver-length top Picatinny rail is installed. A fixed front sight tower is present; no rear sight is installed.
The rifle uses a semi-automatic, direct blowback action within a robust polymer receiver. The UMP-pattern, skeletonized folding stock and polymer construction keep weight balanced. Capacity is 25+1 with the included magazine, and length of pull measures 15.0 inches.