FN P90

Lore & Background

Development of the P90 began in 1986, and production commenced in 1990, when it was known as the Project 9.0 (from which the '90' in its name is derived). The weapon was designed in conjunction with the FN 5.7×28mm NATO ammunition. The original 5.7×28mm cartridge, called the SS90, propelled a 1.5 g (23 grain) plastic-core projectile at a muzzle velocity of roughly 850 metres per second (2,800 ft/s). A modified version of the P90 with a magazine adapted to use the shortened SS190 ammunition was introduced in 1993, and the Five-seven pistol was subsequently introduced as a companion weapon using the same 5.7×28mm ammunition.

The P90 is a selective fire, straight blowback-operated weapon that fires from a closed bolt. Its design incorporates several innovations, such as a unique top-mounted magazine and FN's small-caliber, high-velocity 5.7×28mm ammunition. The weapon is fully ambidextrous, with the charging handle, magazine release, and backup iron sights symmetrically distributed on both sides. Spent cartridge casings eject downward through a chute behind the grip. The P90 can be fitted with a sling, and a hollow compartment inside the rear of the frame allows for storage of a cleaning kit.

Further development led to the P90 TR model, introduced in late 1999, which has a MIL-STD-1913 (Picatinny) triple rail interface for mounting accessories. Additional integrated features include interchangeable visible or infrared laser and tritium light sources. The P90 requires minimal maintenance and can be disassembled quickly and easily.

Reader's Guide

The P90 was developed by FN Herstal in response to NATO requests for a replacement for the 9×19mm Parabellum cartridge and associated pistols and submachine guns. NATO called for two types of weapons chambered for a new cartridge—a shoulder-fired personal defense weapon and a handheld weapon—to provide personal protection in last-resort situations. The P90 was the first shoulder-fired PDW to respond to this requirement. In 2002 and 2003, NATO tests compared the 5.7×28mm cartridge with the HK 4.6×30mm cartridge; a group of experts from Canada, France, the United Kingdom, and the United States concluded that the 5.7×28mm was statistically the more efficient cartridge, but NATO countries could not reach consensus to standardize it, halting the process indefinitely. The 5.7×28mm was eventually standardized by NATO in February 2021.

The P90 is currently in service with military and police forces in over 40 nations, including Austria, Brazil, Canada, France, Greece, India, Malaysia, Poland, and the United States. In the United States, it is used by over 200 law enforcement agencies, including the U.S. Secret Service. The standard selective fire P90 is restricted to military, law enforcement, or holders of certain Federal Firearms Licenses with the Special Occupational Tax. Since 2005, a semi-automatic version with a longer barrel has been offered to civilian users as the PS90.

Did You Know?

• The P90 was originally known as Project 9.0 during development, from which the '90' in its name is derived.
• The P90 ejects spent cartridge casings downward through a chute behind the grip, keeping them out of the shooter's line of sight.
• The P90 is the most compact fixed-stock submachine gun ever made, with an overall length of 500 mm.
• The 5.7×28mm cartridge was eventually standardized by NATO in February 2021.