In Residue Processing, it can be retrieved from a security guard being eaten by a Barnacle.
The weapon is suited to taking out weaker enemies such as Zombies, Headcrabs, and Houndeyes. As it is very accurate at long range, the Pistol is ideal for picking off enemies from a distance where they have a hard time counterattacking. It is one of the few weapons that is able to fire underwater. It shares ammo with the Submachine Gun, which makes it very easy to find ammunition for it throughout the game. The latter is recommended to be used only at close range. Its primary attack fires accurate shots at a slow rate, while the secondary attack fires quick but less accurate bullets. It has both primary and secondary firing options.
The Pistol is among one of the first weapons received, acquired in the early stages of the games.