The slide on the majority of fully/

semi-automatic pistol A semi-automatic pistol is a type of repeating single- chamber handgun ( pistol) that automatically cycles its action to insert the subsequent cartridge into the chamber (self-loading), but requires manual actuation of the trigger to ac ...

s is the upper part that reciprocates ("slides") with

recoil Recoil (often called knockback, kickback or simply kick) is the rearward thrust generated when a gun is being discharged. In technical terms, the recoil is a result of conservation of momentum, as according to Newton's third law the force r ...

during the gun's operating cycle. It serves as the

bolt The BOLT Browser was a web browser for mobile phones including feature phones and smartphones that can run Java ME applications. The BOLT Browser was offered free of charge to consumers and by license to mobile network operators and handset manuf ...

carrier group (BCG) and partly as the receiver, and generally houses the firing pin/

striker Striker or The Strikers may refer to: People *A participant in a strike action *A participant in a hunger strike *Blacksmith's striker, a type of blacksmith's assistant *Striker's Independent Society, the oldest mystic krewe in America People wi ...

, the extractor and frequently also the barrel, and provides a mounting platform for

iron Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in ...

and

optical sight A sight is an aiming device used to assist in visually aligning ranged weapons, surveying instruments or optical illumination equipments with the intended target. Sights can be a simple set or system of physical markers that have to be aligne ...

s. Through the principles of

short recoil Recoil operation is an operating mechanism used to implement locked breech, autoloading firearms. Recoil operated firearms use the energy of recoil to cycle the action, as opposed to gas operation or blowback operation using the pressure of the ...

simple blowback Blowback is a system of operation for self-loading firearms that obtains energy from the motion of the cartridge case as it is pushed to the rear by expanding gas created by the ignition of the propellant charge. Several blowback systems exist wit ...

operations, the slide is moved backwards with each shot by the energy of expanding gasses caused by the combusting

propellant A propellant (or propellent) is a mass that is expelled or expanded in such a way as to create a thrust or other motive force in accordance with Newton's third law of motion, and "propel" a vehicle, projectile, or fluid payload. In vehicles, the ...

(often a nitrocellulose-based

smokeless powder Finnish smokeless powderSmokeless powder is a type of propellant used in firearms and artillery that produces less smoke and less fouling when fired compared to gunpowder ("black powder"). The combustion products are mainly gaseous, compared to ...

, very rarely

black powder Gunpowder, also commonly known as black powder to distinguish it from modern smokeless powder, is the earliest known chemical explosive. It consists of a mixture of sulfur, carbon (in the form of charcoal) and potassium nitrate ( saltpeter) ...

). Because the slide is spring-loaded, once at the rearmost position, the spring tension will push it back towards the front. Generally, this slide movement cycle serves three functions: the extractor will empty the chamber by pulling out the spent casing from the previous shot (which then gets removed out of the gun by the ejector), the slide

inertia Inertia is the idea that an object will continue its current motion until some force causes its speed or direction to change. The term is properly understood as shorthand for "the principle of inertia" as described by Newton in his first law o ...

will cock the

hammer A hammer is a tool, most often a hand tool, consisting of a weighted "head" fixed to a long handle that is swung to deliver an impact to a small area of an object. This can be, for example, to drive nails into wood, to shape metal (as ...

to prepare for the next shot, and the bolt will push a new cartridge from the magazine into the chamber when the slide comes back forward. This action cycle will be repeated for continued firing as long as the magazine contains rounds and there is no failure to extract/

eject Ejection or Eject may refer to: * Ejection (sports), the act of officially removing someone from a game * Eject (''Transformers''), a fictional character from ''The Transformers'' television series * "Eject" (song), 1993 rap rock single by Senser ...

(which causes

stovepiping Stovepiping (also stove piping) is a metaphorical term which recalls a stovepipe's function as an isolated vertical conduit, and has been used, in the context of intelligence, to describe several ways in which raw intelligence information may be ...

and double-feeding),

failure to feed A firearm malfunction is the failure of a firearm to operate as intended for causes other than user error. Malfunctions range from temporary and relatively safe situations, such as a casing that did not eject, to potentially dangerous occurrences ...

, or out-of-battery malfunction. Fully/semi-automatic air pistols' slides operate with similar principles as firearms, except they utilize pneumatic energy from compressed gas (usually air, ,

propane Propane () is a three-carbon alkane with the molecular formula . It is a gas at standard temperature and pressure, but compressible to a transportable liquid. A by-product of natural gas processing and petroleum refining, it is commonly used as ...

refrigerant A refrigerant is a working fluid used in the refrigeration cycle of air conditioning systems and heat pumps where in most cases they undergo a repeated phase transition from a liquid to a gas and back again. Refrigerants are heavily regulate ...

s) instead of burning propellants. Because air pistols typically have much lower muzzle energy than firearms, there is less recoil that can be used to operate the slide. However, because airgun pellets/ shots have no casings that needed to be extracted (unlike firearm cartridges), a very brief slide movement is sufficient to cycle the action and load the subsequent shot, so only a small amount of energy is needed to move the slide. On most modern designs, once the magazine is empty, a slide stop will catch and lock the slide at its rearmost position, and will only be released to move back forward after the slide release is depressed. Having the slide automatically loading the chamber and cocking the hammer/striker with each prior shot is essential for the function of

double-action Double action (or double-action) refers to one of two systems in firearms where the trigger both cocks and releases the hammer. * Double-action only (DAO) firearms trigger: The trigger both cocks and releases the hammer. There is no single-actio ...

single-action A trigger is a mechanism that actuates the function of a ranged weapon such as a firearm, airgun, crossbow, or speargun. The word may also be used to describe a switch that initiates the operation of other non-shooting devices such as a tr ...

pistols.

Hammerless A hammerless firearm is a firearm that lacks an exposed hammer or hammer spur. Although it may not literally lack a hammer, it lacks a hammer that the user can pull directly. One of the disadvantages of an exposed hammer spur is the tendency to ...

and striker-fired pistols, lacking external hammer that can be directly manipulated, need to have the whole slide manually pulled back to cock the hammer/striker if the gun is not already cocked for firing.

See also