Trigger: p90, submachine gun, bullpup
The FN P90 is a personal defense weapon (PDW) developed by the Belgian company FN Herstal in response to a NATO request for a compact firearm capable of defeating body armor. Designed between 1986 and 1990, the P90 was created alongside the proprietary 5.7×28mm cartridge, aiming to replace traditional 9×19mm Parabellum firearms with a more effective solution.
The 5.7×28mm cartridge was engineered to offer higher velocity, greater range, and improved accuracy over the 9×19mm round. Notably, it was designed to penetrate soft body armor, addressing a critical need identified by NATO for personal defense weapons. In 2002 and 2003, NATO conducted evaluations to standardize a PDW cartridge, comparing FN's 5.7×28mm with Heckler & Koch's 4.6×30mm. The tests concluded that the 5.7×28mm was "undoubtedly" the more efficient cartridge. However, standardization was delayed due to objections from some member nations and was only finalized in February 2021.
The P90's design features a bullpup configuration with a top-mounted 50-round magazine, integrated reflex sight, and fully ambidextrous controls. Its compact size allows for easy maneuverability in confined spaces, making it suitable for vehicle crews, support personnel, and special forces.
The original model, often referred to as the P90 Standard, featured an integrated non-magnifying reflex sight designed by Ring Sights. This sight was built directly into the top of the receiver, providing users with a streamlined aiming solution. In 1999, FN introduced the P90 TR (Triple Rail) variant, which replaced the integrated reflex sight with a receiver-mounted triple MIL-STD-1913 (Picatinny) rail system. The top rail allowed for the attachment of various optical sights, while the two side rails accommodated accessories such as tactical lights or laser aiming devices. This design offered users greater flexibility in customizing their weapon’s configuration. Additionally, FN released the P90 USG (United States Government) model, which retained the integrated reflex sight but featured an aluminum housing and a revised reticle.
The P90 and its 5.7×28mm cartridge have been adopted by military and law enforcement agencies in over 40 countries, reflecting its effectiveness and versatility in modern combat and security operations.