The Calico M-100P is semi-automatic pistol chambered in .22 LR that fires much faster than any other handgun. Claire found a pair of these on a zombified Security force agent early in the game and they give her the ability to fire at two different enemies simultaneously. They take up two inventory slots and use a percentage base ammunition count similar to the automatic weapons found throughout the series. No extra ammunition is ever found for these weapons during the course of the game.
This weapon is slightly powerful and fires in 3-rounds burst in quick succession. Claire can aim at two enemies at once and attack. The player can also change targets by holding the Ready Weapon button and pressing the L1 button. As no spare magazines are ever found for this weapon, it is effectively useless after it has run out of ammunition.