The GSh-18 (Cyrillic: ГШ-18 ) is a 9mm semi-automatic pistol developed in the early 1990s at the KBP Instrument Design Bureau in Tula. The pistol's name is derived from its designers—Gryazev and Shipunov, and the number 18 denotes the magazine capacity. It is also designed to fire the new Russian 9x19mm 7N21 and 7N31 (Cyrillic: 7Н21 and 7Н31) +P+ armor-piercing rounds.
For 2011, KPB Design Bureau announced a possible marketing of a civilian version of the GSH 18 with modified trigger and firing pin to comply with Russian gun law. This information was confirmed at the 2011 IWA show where a sample gun was displayed.
The GSh-18 is a short recoil-operated, locked breech pistol. The weapon has an unusual cam-rotated barrel with 10 locking lugs. The GSh-18 is striker-fired and features a pre-set trigger that pre-cocks the pistol when the slide recoils after firing a shot. The striker firing pin is then fully cocked by pulling the trigger back to the rear. With the standard bullets, GSh-18 punches all known bullet-proof vests (including army). With the armor-piercing bullets 7N31 the gun punches 8 mm of steel (15–20 meters of distance). GSh-18 contains only 17 parts (for example the Glock 17 contains 34 parts).