The Heckler & Koch UMP

The UMP was designed in the 1990s by Heckler & Koch (HK), as a cheaper, lighter alternative to the MP5, which made heavy use of polymers. The UMP first entered production in 2000. It was designed primarily for use by American military and law enforcement units, as the MP5 was not available in .45 ACP, a round which was popular in the United States, but not in Europe. Despite the UMP's improvements and reduced cost, it did not replace the MP5, which ended up outselling the UMP.