The StA-18 Pistol is the standard-issue Helghast pistol manufactured by Stahl Arms. It fires the 9.2x20mm cartridges, as written on the magazine, but holds only 12 rounds in a helical magazine on the front of the weapon. In Killzone 1 where it had the name IvP-18 Tropov Machine Pistol, it had a burst-fire feature, similar to the real world Berretta 93R; however, this feature was removed from Killzone 2. The weapon is still an effective sidearm in the campaign, however, as it packs as much punch as an M4 Revolver, and comes with more ammo as well. You can only find it on the ISA Cruiser level and the Suljeva Village level in the campaign. First appearance: Salamun Bridge: Bridge East. It is one of three Helghast weapons that do not have a bullpup design. It bears similarities to the real-life Mateba Autorevolver.
In the Killzone 2Multiplayer and Killzone 3Multiplayer mode, the StA-18 is the first secondary weapon & pistol for every class. Overall, it is a substantially less powerful weapon than the M4 Revolver, requiring many shots into an enemy in order to kill him. However, it has a higher rate of fire (as well as larger magazine size) than the M4 Revolver. Though the StA-18 requires more shots to the body to kill an enemy than the M4 Revolver, headshots are quite deadly, usually requiring only 1 or 2 shots to kill an enemy. The closer an enemy is, the more effective headshots are while using the STA18. For skilled players, it is still a very reliable and dependable weapon.
The StA-18's 9.2 mm caliber could possibly be a reference to the movie Red Heat where the main protagonist (a Soviet cop played by Arnold Schwarzenegger) uses a fictional Soviet pistol, the Podbyrin (actually a modified Desert Eagle) chambered with the fictional 9.2 mm cartridge.