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Autoloading - Full Automatic Pistols

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Autoloading - Full Automatic Pistols

Photo of a Glock G18 full automatic pistol
Glock G18 full automatic pistol
RCMP Firearms Reference Table< (see reuse policy).

With a single trigger pull, pistols in full automatic mode (with trigger fully depressed and cartridges in the feed system) do the following:

  • Feed cartridges
  • Fire the shot
  • Extract and eject cartridge cases
  • Continue the cycle (until ammunition is depleted or trigger is released)

Full automatic pistols fall into two categories:

  • Full automatic by design, with a selector switch that allows the shooter to fire in the full or semiautomatic mode
  • Semiautomatic pistol modified to fire full automatic

Single- and Multibarreled Pistols

Thompson/Center pistol
Thompson/Center pistol
Courtesy of Forensic Technology Inc. Gunsights Pro 3.0 (see reuse policy).

Pistols may be designed to fire only one shot at a time. These types of pistols may have one or more barrels. With each pull of the trigger, a single shot is fired. When a barrel is emptied after firing, the shooter must manually unload and reload.

American Derringer
American Derringer
Courtesy of Forensic Technology Inc. Gunsights Pro 3.0 (see reuse policy).

The most common design is the break open pistol, which has a locking device that must be released to allow the chamber area of the barrel(s) to tip up and away from the breech for loading and unloading.

Trigger Systems

Colt 1911A1 Single action pistol
Colt 1911A1 Single action pistol
Courtesy of Forensic Technology Inc. Gunsights Pro 3.0 (see reuse policy).

Single- or multibarrel pistols have trigger systems similar to revolvers.

Semiautomatic and full automatic pistols can have

  • single-action trigger system,
  • double-action trigger system,
  • double-action-only trigger system.

 

 

 

Beretta model 92FS double action pistol
Beretta model 92FS double action pistol
Courtesy of Forensic Technology Inc. Gunsights Pro 3.0 (see reuse policy).

The single-action trigger is the most common system. The only function of the trigger is to discharge the firearm. The firearm cannot be cocked by use of the trigger. In firearms with an external hammer, the hammer may be manually cocked; in striker-fired weapons,the slide must be pulled to the rear and released to cock the firearm.

In the double-action system, the hammer can be at rest. Pulling the trigger cocks the hammer and fires the weapon. After the first shot is fired in double-action mode the remaining shots are fired in the single-action mode. This occurs because the firing cycle cocks the firearm after each shot until the hammer is manually placed at rest.

Taurus PT24/7 Double action only
Taurus PT24/7 Double action only
Courtesy of Forensic Technology Inc. Gunsights Pro 3.0 (see reuse policy).

The double-action-only (DAO) trigger system cocks and fires the firearm after each shot. The hammer returns to the rest position after each shot.

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