What is Five-seven?
1.
Designed as the sidearm to accompany the P90 PDW, the Five-seveN pistol by Fabrique Nationale uses the same 5.7 x 28 mm cartridge as the P90. Despite the bulky nature of the ammo, the 20-round magazine can still be fitted into a comfortably-sized grip. The pistol itself was originally a striker-fired double-action only one, although the "tactical" version introduced a single-action mechanism. Operating by the traditional Browning breech-lock method, the Five-seveN has very little recoil for a combat pistol, rougly 2/3 of a gun of equal bulk in 9 mm Parabellum. With a muzzle velocity of 2100 ft/sec, the Five-seveN is just as capable of piercing armor as the P90. And the capitalization of the N in "seveN" is undoubtedly a marketing gimmick on the part of FN.
2.
Trusty pistol of Sam Fisher
Solid Snake} used a H&K mk23 SOCOM