PP-90

The PP-19 Bizon is a Russian submachine gun developed in the 1990s at the Izhmash factory by a design team including Victor Kalashnikov, the son of Mikhail Kalashnikov. Its most distinctive feature is the underbarrel helical magazine with a capacity of 64 rounds of 9x18mm Makarov ammunition, giving it exceptional firepower in a compact package. The Bizon shares over 60% parts commonality with the AKS-74U, from which it was derived, including its receiver, stock, and trigger group. It uses a simple blowback operating mechanism and fires from a closed bolt, with semi-automatic and fully automatic firing modes. The helical magazine's compact profile avoids the awkward length of conventional high-capacity magazines, making the Bizon surprisingly maneuverable in tight spaces.

The Star Z-70B is a selective-fire submachine gun manufactured by Star Bonifacio Echeverria of Spain. It was chambered in 9x19mm Parabellum and used a blowback action. The weapon was an improved version of the earlier Z-62 model. It featured a telescoping bolt and a side-folding metal stock. The Z-70B was adopted by the Spanish military and other nations.

The United Defense M42 is an American submachine gun designed by Carl Swebilius. It was produced for the Office of Strategic Services during World War II. The M42 uses a blowback action chambered in 9x19mm Parabellum and feeds from a 25-round box magazine. It features a wooden stock, a perforated barrel jacket, and a folding magazine well. The weapon was designed to be compact and concealable for clandestine operations. It was one of the first submachine guns designed specifically for intelligence and special operations work.