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. 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. Recall In 2000, H&K recalled certain UMP and USC serial numbers due to faulty operating handles. The faulty handles, made of polymer, could break off, making the weapons inoperable. ==Design details==

The UMP is a blowback-operated, magazine-fed submachine gun that fires from a closed bolt. The closed bolt design increases the accuracy, which is particularly desirable in a law enforcement context. The UMP was originally designed for larger cartridges such as the .40 S&W and .45 ACP, to provide more stopping power against unarmoured targets, with slightly lower effectiveness at longer ranges. A larger cartridge produces more recoil and makes it harder to control in fully automatic fire. To mitigate the excessive recoil, Heckler & Koch designed the UMP to have a cyclic rate of around 600 rounds per minute, though the rate of fire increases up to 700 rounds per minute if (+ P) ammunition is used. Its predominantly polymer construction reduces both its weight and the number of parts susceptible to corrosion. The UMP is available in four trigger group configurations, featuring different combinations of semi-automatic, 2-round burst, fully automatic, and safe settings. It features a side-folding buttstock to reduce its length during transport. When the last round of the UMP is fired, the bolt locks open, and can be released via a catch on the left side. The iron sights consist of an aperture rear sight and a front ring with a vertical post. It can mount four Picatinny rails (one on top of the receiver, and one on the right, left, and bottom of the handguard) for mounting accessories such as optical sights, tactical lights, or laser sights. Vertical foregrips can be attached to the bottom rail for better control during burst and automatic fire. == Variants ==

The UMP is interchangeable between three different calibres: The UMP9, chambered in 9×19mm Parabellum The UMP40, chambered in .40 S&W The UMP45, chambered in .45 ACP Apart from the different chambering, all versions feature the same design model, the exterior differences being the curved magazine used on the UMP9, while both the UMP40 and UMP45 each use a straight magazine. All three versions of the weapon can be cross-converted to any of the round chamberings by replacing the bolt, barrel, and magazine. Originally available in grey, as of 2008 the USC came only in an all-black finish. Production of the USC was halted in 2013. In 2018, H&K announced a limited production run of new USC rifles. Clones • Omega Gideon Shadow – American clone of the UMP released in 2017. • Tommy Built Tactical TMP/KSM – American clone of the UMP. • DefGunz DEF9 – American clone of the UMP receiver released in 2024. • S5 Tactical SMP – American clone of the UMP receiver released in 2025. ==Users==

operator with a UMP9 == See also ==