With unloaded magazine:
The Heckler & Koch UMP (Universale Maschinenpistole, German for "Universal Submachine Gun") is a submachine gun developed and manufactured by Heckler & Koch. The UMP has been adopted by various agencies such as the U.S. Customs and Border Protection. Heckler & Koch developed the UMP as a lighter and cheaper successor to the MP5, though both remain in production.
The UMP is a blowback-operated, magazine-fed submachine gun firing from a closed bolt.
As originally designed...