All Firearms have three basic groups of parts; these include the Action, The Stock, and the Barrel.
ACTION: The action is really the guts of the gun. It includes all the moving parts that load, fire, and eject the firearms shells or cartridges.
STOCK: The stock (or Handle) of the gun in composed of two pieces (the Butt and the fore-end).
BARREL: A guns Barrel is the long metal tube, bored out to provide an exit path for the discharging projectile. Once the projectile is fired, it’s forced down the barrel and out of the muzzle by expanding gas forces. In a rifle or a handgun, the bullet travels through the barrel; in Shotguns the Shot or the Slug is shot through the barrel.
Shotguns are a type of firearm that fires shells containing either shot (small round pellets) or a slug (a solid projectile). Below are the parts of a common pump-action shotgun.
Handguns are handheld short-barreled firearms. The picture below shows the common components found on a pistol and a revolver.
Bore: The bore in the inside of the gun’s barrel through which the projectile travels when fired.
Breech: The Breech is the area of the firearm that contains the rear end of the barrel, where the cartridge is inserted.
Cylinder: The Cylinder is the part of a revolver that holds cartridges in separate chambers. The Cylinder of a revolver rotates as the gun is cocked, brining each chamber into alignment with the barrel.
Grip: The Grip is the portion of a handgun that’s used to hold the firearm.
Hammer: The Hammer on a revolver is the part that strikes the firing pin or the cartridge primer directly, detonating the primer which discharges the gun.
Magazine: A Magazine is a spring-operated container that can be fixed or detachable, which holds cartridges for a repeating firearm.
Muzzle: The muzzle of a gun is the front end of the barrel where the projectile exits the firearm.
Trigger: The Trigger is the lever that’s pulled or squeezed to initiate the firing process.