The MP5 is a 9x19mm Parabellum submachine gun, developed in the 1960s by a team of engineers from the German small arms manufacturer Heckler & Koch GmbH (H&K) of Oberndorf am Neckar. There are over 100 variants of the MP5, including some semi-automatic versions.
The MP5 is one of the most widely used submachine guns in the world, having been adopted by 40 nations and numerous military, law enforcement, intelligence, and security organizations. It was widely used by SWAT teams in North America, but has since been supplanted by M16 variants in the 21st century.
In 1999, Heckler & Koch developed the Heckler & Koch UMP, the MP5’s successor; both are available as of 2019, but the UMP has not met the same level of success.
The primary version of the MP5 family is the MP5A2, which is a lightweight, air-cooled, selective fire delayed blowback operated 9×19mm Parabellum weapon with a roller-delayed bolt. It fires from a closed bolt (bolt forward) position.
The fixed, free floating, cold hammer-forged barrel has 6 right-hand grooves with a 1 in 250 mm (1:10 in) rifling twist rate and is pressed and pinned into the receiver.
The MP5 has a hammer firing mechanism. The trigger group is housed inside an interchangeable polymer trigger module (with an integrated pistol grip) and equipped with a three-position fire mode selector that serves as the manual safety toggle. The “S” or Sicher position in white denotes weapon safe, “E” or Einzelfeuer in red represents single fire, and “F” or Feuerstoß (also marked in red) designates continuous fire. The SEF symbols appear on both sides of the plastic trigger group. The selector lever is actuated with the thumb of the shooting hand and is located only on the left side of the original SEF trigger group or on both sides of the ambidextrous trigger groups. The safety/selector is rotated into the various firing settings or safety position by depressing the tail end of the lever. Tactile clicks (stops) are present at each position to provide a positive stop and prevent inadvertent rotation. The “safe” setting disables the trigger by blocking the hammer release with a solid section of the safety axle located inside the trigger housing.
In the early 1970s, HK introduced a conversion kit for the MP5 that enables it to use rimfire ammunition (.22 LR). This unit consists of a barrel insert, a bolt group and two 20-round magazines. This modification reduces the cyclic rate to 650 rounds/min. It was sold mostly to law enforcement agencies as a way to train recruits on handling the MP5. It used ammunition that was cheaper and had a lower recoil than 9×19mm Parabellum. This reduced training costs and built up skill and confidence in the operators before transitioning them to the full-bore model.
The MP5A2 has a fixed buttstock (made of a synthetic polymer), whereas the compact MP5A3 has a retractable metal stock. The stockless MP5A1 has a buttcap with a sling mount for concealed carry; the MP5K series was a further development of this idea.
The MP5A4 (fixed stock) and MP5A5 (sliding stock) models, which were introduced in 1974, are available with four-position trigger groups. The pistol grips are straight, lacking the contoured grip and thumb groove of the MP5A1, MP5A2, and MP5A3. The selector lever stops are marked with bullet pictograms rather than letters or numbers (each symbol represents the number of bullets that will be fired when the trigger is pulled and held rearward with a full magazine inserted in the weapon) and are fully ambidextrous (the selector lever is present on each side of the trigger housing). The additional setting of the fire selector, one place before the fully automatic setting, enables a two or three-shot burst firing mode.
A variant with the last trigger group designated the MP5-N (N—Navy) was developed in 1986 for the United States Navy. This model has a collapsible stock, a tritium-illuminated front sight post and a 225 mm (8.9 in) threaded barrel for use with a stainless steel sound suppressor made by Knight’s Armament Company together with quieter subsonic ammunition. It had ambidextrous controls, a straight pistol grip, pictogram markings, and originally had a four-position selector (Safe, Semi-Auto, 3-Round Burst, Full Auto). This was replaced with a similar three-position ambidextrous selector after an improperly-reassembled trigger group spontaneously fired during an exercise. The “Navy”-style ambidextrous trigger group later became standard, replacing the classic “SEF” trigger group.
In late 2013, Heckler & Koch unveiled the MLI (Mid Life Improvement) version of the MP5. It is fitted with a tri-rail foregrip, a quick-release-optic mount, an MP5F stock standard, and comes in with the new RAL8000 (Yellow-Brown) colour scheme.
|Action||Roller-delayed blowback, closed bolt|
|Rate of fire||
|Effective firing range||
|Feed system||15, 30 or 40 round detachable box magazine and 100-round Beta C-Mag drum magazine|
|Sights||Iron sights. Rear: rotary drum; front: hooded post|