FN P90 Country Belgium Type Submachine gun Manufacturer Fabrique Nationale Introduction 1987 Specifications Weight 2.54 kg (5.6 lb) empty 3.0 kg (6.6 lb) loaded[1] Length 500 mm (19.7 in) Barrel length 263 mm (10.4 in)[2] Width 55 mm (2.2 in) Height 210 mm (8.3 in) Cartridge 5.7x28mm[3] Action Straight blowback, closed bolt Rate of fire 900 rounds/min Muzzle velocity 716 m/s (2,349 ft/s) with SS190 Effective range Sights fixed for 150 m Feed system 50-round detachable box magazine Sights Tritium-illuminated reflex sight, back-up iron sights

The P90 is a Belgian designed 5.7x28mm submachine gun, developed between 1986-1987 by Stéphane Ferrard at Fabrique Nationale de Herstal. The weapon’s name is an abbreviation of Project, and the number 90, which specifies a weapon system of the 1990s.

The submachine gun contains several innovative features, including the proprietary ammunition. It uses the new, 5.7x28mm cartridge, which has a greater penetrating capability, lethal range and flatter trajectory than most other pistol caliber cartridges such as the NATO-standard 9x19mm Parabellum round. Initially the weapon used a 5.7x28mm SS90 cartridge (with a lightweight, roundnose, jacketed projectile and a polymer core), as well as tracer, training (reduced range), sub-caliber (increased velocity and effective range of up to 250 m) and blank ammunition. The first prototype firing this ammunition was completed in October 1986, and over 3,000 submachine guns were produced in this configuration until 1993 in a low-rate initial production run. Meanwhile, FN revised the ammunition, with the intention of using it in a planned semi-automatic pistol of the same caliber - the Five-seven. The new cartridge, designated the SS190, has a more conventional full metal, plated steel jacket, lead core and steel/aluminum penetrator. Several other projectiles were also developed for the new cartridge, including the L191 tracer round, a subsonic SB193 bullet for sound-suppressed P90 firearms and blank ammunition. This modified version of the P90, adapted to use the new ammunition was introduced in 1993.

The P90 is considered a Personal Defense Weapon (PDW), and is designed as a compact but powerful firearm for vehicle drivers, operators of crew-served weapons, support personnel, special operators and anti-terrorist units.