The submachine gun is a small and light kind of firearm. It was invented during World War I and has made its stay in close-quarter combat since then. It was designed to fulfill the concept of maneuverability in tight spaces and has revolutionized urban warfare and special operations.
A classic example of an SMG is the Heckler & Koch MP5. The MP5 has become famous for being reliable and versatile throughout most military, law enforcement, and special forces units worldwide. Its compactness and high rate of fire make it stand out from all other weapons in times of fast engagement. Elite units such as the United States Navy SEALs, the German GSG9, and the British SAS continue to expand their operational record.
The MP5 series has a few remarkable variants. Coming in with an even shorter barrel, the MP5K than the MP5K, it also has a forend that is considerably shorter to still further compress the already compact submachine gun. It lacks a stock and features a supporting vertical grip handle which is encased in rubber to provide additional support when firing. The MP5K model itself has a few sub-variants; the MP5KA1 has a cleaner-upper receiver, while the three-round burst fire-enabled MP5KA4 also exists. The MP5K-N version, developed especially for the United States Navy with support for a threaded suppressor, and the MP5K-PDW—”Personal Defense Weapon”, with a hinged folding stock and a forward vertical grip.
There are also integrally suppressed variants, designated by the suffix MP5SD. The MP5SD1 has no stock; the MP5SD2 has a full stock; the collapsing stock version is the MP5SD3; the MP5SD4 has a three-round burst feature. The MP5SD-N1 and MP5SD-N2 are US Navy models equipped with stainless steel suppressors made by Knight’s Armament Company.
Although created to fulfill the same battlefield niche, SMGs are indispensable for certain specialized applications and by law enforcement agencies to this day, while weapons such as the MP5 show virtually unrivaled superiority because of their extremely high rate of fire and compact size of firepower during close-quarters combat.
Another of the SMGs worth noting is the UMP, developed by HK to provide a less costly alternative to the MP5 series. The UMP is designed to provide versatility and low weight without giving away either reliability or accuracy. It has caliber modularity so it may be easily purposed in 9mm, .40 S&W, and .45 ACP. In contrast to the highly complex roller-delayed action of the MP5, the UMP uses a much-simplified straight blow-back action system, making it extremely mission-configurable.
Some of the most famous users of the UMP include the Australian Special Operations Forces, Jordanian SOF, Brazilian Army, Marine Corps SOF, and the U.S. Customs and Border Protection. Out of all variants, the UMP9 and UMP40 are quite well-known. The UMP45 finds application with the Georgian SOF and the U.S. 5th Special Forces Group.
The civilian market has been provided with adaptations of these military-grade SMGs. While civilian copies of the MP5 were available as early as the HK94 and SP89, the civilian version of the UMP did not appear until 1999, as the HK USC. The USC is a “civilian utility carbine” chambered for the .45 ACP cartridge, with a carbon fiber reinforced polymer body, but its ergonomics are less than ideal, due to the need to satisfy the “sporting purposes” provision of the Gun Control Act of 1968.
In conclusion, submachine guns have, of course, made a greater mark on the world of firearms. From their very “inception” in the trenches of World War I to modern applications in special operations and law enforcement, these compact firearms remain a mainstay tool in CQB. In particular, the MP5 and UMP have come to symbolize the evolution and impact of the SMG in modern warfare.