Types of actions

All cartridge firing firearms used for target shooting or hunting have the following things in common: the cartridge is fed into the chamber; it is locked there by the action; the action is cocked; it is fired; it is unlocked; and the empty cartridge case is extracted and ejected.

Cutaway drawings of four different types of cartridge. Clockwise from top left: a) A shot cartridge; b) A centrefire cartridge; c) A rimfire cartridge; d) A rifled slug for use in a shotgun (single projectile).

 

Common firearm actions, from top to bottom: a) A bolt action; b) A lever action; c) A pump action; d) a self loading.

The bolt action is one of the simplest and most trouble-free firearm actions. Starting from the unloaded condition, the action is unlocked by lifting the bolt handle and pulling it back. A cartridge is fed into the chamber by pushing the bolt forward. The bolt handle is then turned downwards, locking the bolt and cartridge in place. A firing pin is usually cocked by movement of the bolt or bolt handle, and when the trigger is squeezed the pin is released, firing the cartridge. The empty cartridge case is then ejected by lifting the bolt handle again and pulling the bolt back.

The lever action works on the same basic principle, except that a lever is pushed down to unlock the bolt and move it backwards. This movement also cocks the action. When the lever is pulled upwards again it feeds a cartridge into the chamber and locks, ready to be fired by the trigger. After the cartridge is fired the empty case is ejected by once more pushing the lever down.

pump action is again similar. A pump slide is pulled backwards to open the action and cock it. When the slide is pushed forward the action feeds a fresh cartridge, locks, and is ready to fire.

self loading also known as a semi-automatic action, operates in the same way as the above firearms. However, ejection and loading is carried out automatically by the force of either the recoil or by gas pressure. Because of the automatic reloading, a cartridge is ready to be fired each time the trigger is squeezed.

The most common shotguns in Australia are the breakopen variety where the barrel(s) hinge downwards. There are over-and-under, side-by- side and single barrel shotguns.
Some shotguns are self loading or pump action.