FN 5.7×28mm

[10] Unlike many new cartridges, it has no parent case; the complete package was developed from scratch by FN.

[13] By 2006, FN's 5.7×28mm firearms—the P90 PDW and Five-seven pistol—were in service with military and police forces in over 40 nations throughout the world.

[14] In the United States, 5.7×28mm firearms are currently used by numerous law enforcement agencies, including the U.S. Secret Service.

[27] A United States patent application for the projectile design used in the SS90 was filed by FN's Jean-Paul Denis and Marc Neuforge in 1989.

[6] The SS190 uses a 2.7 mm (0.11 in) shorter projectile with a mass of 2.0 g (31 gr), which has, when fired from the P90, a muzzle velocity of roughly 716 m/s (2,350 ft/s; Mach 2.1).

[31] The shorter length of the SS190 projectile allows it to be more conveniently used in the 5.7×28mm FN Five-seven pistol, which was also being developed at that time.

[6] Several specialized 5.7×28mm varieties were also developed alongside the SS190, such as the L191 tracer round and the subsonic SB193 bullet for sound-suppressed use.

[33] In 2002 and 2003, NATO conducted a series of tests with the intention of standardizing a PDW cartridge as a replacement for the 9×19mm Parabellum.

[12][29] As a result, both the 4.6×30mm and 5.7×28mm cartridges (and the associated weapons) have been independently adopted by various NATO countries, according to preference; both the P90 and Five-seven are currently in service with military and police forces in over 40 nations throughout the world.

[12] In 2004, the SS192 hollow-point cartridge was introduced to civilian shooters alongside the new IOM variant of the Five-seven pistol.

[45][49] One of the design intents of the SS190 variety of this cartridge was that it have the ability to penetrate Kevlar protective vests—such as the NATO CRISAT vest—that will stop conventional pistol bullets.

[31][32] However, sporting variants of the 5.7×28mm are classified by the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) as not armor-piercing.

[11][44][50][51] However, some are skeptical of the bullet's terminal performance, and it is a subject of debate among civilian shooters in the United States.

(Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives) rulings, the 5.7×28mm can handle up to 3,450 bar (345 MPa; 50,038 psi) Pmax (the nominal maximum) piezo[clarification needed] pressure.

regulated countries are currently (2018) proof tested at 4,313 bar (431 MPa; 62,555 psi) PE piezo pressure.

[7] Despite the relatively high Pmax the bolt thrust of the 5.7×28mm is on a similar level when compared with traditional service sidearm cartridges.

Photo of a 5.7×28mm SS196SR cartridge next to a quarter and ruler, in a size comparison.
5.7×28mm SS196SR with a quarter and a ruler
Photo of various cartridges, showing from left to right: 9×19mm Parabellum, .40 S&W, .45 ACP, 5.7×28mm, 5.56×45mm NATO, .300 Winchester Magnum, 2.75-inch 12 gauge, and 3-inch 12 gauge
From left to right: 9×19mm Parabellum , .40 S&W , .45 ACP , 5.7×28mm , 5.56×45mm NATO , .300 Winchester Magnum , with 2.75-and-3-inch (70 and 76 mm) 12 gauge shotgun shells
The 5.7×28mm cartridge next to similarly sized cartridges, from left to right: 4.6×30mm , 5.7×28mm, .30 Carbine
5.7×28mm maximum C.I.P. cartridge dimensions in millimeters (mm)
Photo of the L191 cartridge and box. The cartridge has a red-on-black tip, and the box is light brown with a white label.
L191 cartridge and box
Photo of the SS195LF cartridge and box. The cartridge has a plain tip, and the box is plain white with a white label.
SS195LF cartridge and box
Photo of the 5.7×28mm SS197SR cartridge next to a 5.56×45mm NATO cartridge. The 5.56×45mm cartridge is significantly larger.
SS197SR (left) and 5.56×45mm NATO (right)