Pistol slide

It serves as the bolt carrier group (BCG) and partly as the receiver, and generally houses the firing pin/striker, the extractor and frequently also the barrel, and provides a mounting platform for iron and optical sights.

Through the principles of short recoil or simple blowback operations, the slide is moved backwards with each shot by the energy of expanding gasses caused by the combusting propellant (often a nitrocellulose-based smokeless powder, very rarely black powder).

Because the slide is spring-loaded, once at the rearmost position, the spring tension will push it back towards the front.

Because air pistols typically have much lower muzzle energy than firearms, there is less recoil that can be used to operate the slide.

Having the slide automatically loading the chamber and cocking the hammer/striker with each prior shot is essential for the function of double-action/single-action pistols.