The FEG KGP-9 Submachine Gun (SMG) emerged from the Eastern Bloc nation of Hungary during the latter stages of the Cold War period (1947-1991) in the later part of the 1980s. The weapon became a no-frills design which saw no military export nor service outside of the country, being issued primarily to Hungarian military and security forces for close quarters combat / defense. Manufacture was handled locally by Fegyver-es Gepgyar (FEG) (founded in 1891) and involved casting-reinforced pressed steel construction.
At its core, the KGP-9 was a highly conventional SMG through-and-through, firing the readily available 9x19mm Parabellum German pistol cartridge favored by the West (instead of any Soviet-inspired round). The internal action relied on the proven blowback principle utilizing an open bolt design in which the firing pin interacted with a hammer. The outward design was relatively clean and fee of obstructions, having a rectangular receiver and smooth forend. The barrel was shrouded for most of its length though, rather interestingly, this assembly could be replaced by a longer barrel to increase engagement ranges and create a de facto carbine assault weapon out of the base SMG. The wire shoulder stock was set on a hinge to allow it to be folded away (over the receiver) for a more compact footprint. A shoulder strap could be affixed for easing transport of the weapon.
The feed system relied on a straight, spring-loaded detachable box magazine and the component was inserted ahead of the trigger unit - the box holding up to 25 rounds of 9mm ammunition. Rate-of-fire reached 900 rounds-per-minute with a muzzle velocity of 1,280 feet-per-second. Sighting was handled by a standard front-and-rear iron arrangement. The ejection port was situated along the right side of the frame with the charging handle found on the left side.
Beyond the standard KGP-9 assault weapon was the KGPF-9 which was restricted to Semi-Automatic-Only (SAO) fire for sale in the civilian marketplace.