Action (firearms)

An action is the part of a gun that works.

It loads the bullets. It also locks them in place to fire. After a shot, it moves the old parts out.

Some guns only hold one bullet at a time. You must load them by hand after every shot. These are called single-shot guns.

Other guns can hold many bullets. These are called repeating guns. They use a holder to keep more bullets ready.

A revolver is one kind of repeating gun. It has a spinning part that holds the bullets. This part turns to line up each shot.

There are many ways these parts can move. Some use a handle to pull. Others use a lever to slide. Every action helps the gun work.

An action is the part of a gun that works.

It handles the ammunition. This means it loads, locks, and fires the rounds. It also lets out the old parts after a shot.

Some guns are single-shot. They can only hold one round at a time. You must load them by hand after every shot. One way to do this is a falling block. In this way, a metal block slides up and down.

Another way is a break action. You can break the barrel open to load it.

Other guns are repeating guns. These can hold many rounds. They use a magazine to hold the extra ammunition. A revolver is one kind of repeating gun. It has a cylinder that spins. This cylinder moves each round into place to fire.

Many guns use a bolt to work. A bolt is a part you move by hand. In a bolt-action rifle, you move a handle.

Some people use a straight-pull bolt. This lets them move the bolt quickly without turning it. This helps them shoot faster.

An action is the functional mechanism of a breechloading firearm. It is the part that handles the ammunition cartridges. This includes loading, locking, firing, and ejecting the spent rounds.

Without an action, a gun cannot work. Some older guns called muzzleloaders do not have actions. Instead, they use a lock to ignite the powder.

Actions are very important because they determine how a gun shoots. They can be single-shot or they can be repeating guns.

Single-shot actions can only hold one round of ammunition. You must reload them manually after every single shot. One way this works is the falling block action. In this design, a metal block slides up and down in grooves.

Another way is the pivoting block action. Here, a block is hinged on a pin and tilts down to open the chamber. There is also a break action. This type uses a hinge to let the barrel break open. This exposes the breech so you can load it easily.

Repeating actions allow a gun to hold many rounds. These guns use a magazine, a cylinder, or a belt to hold extra ammunition. A common example is the revolver. A revolver has a rotary cylinder that holds the cartridges. The cylinder rotates to move each round into the right place to fire. Some revolvers are "double-action." This means pulling the trigger can both rotate the cylinder and cock the hammer. This allows the user to shoot many times without extra steps.

Many rifles use a bolt action to work. A bolt is a part that the user moves by hand using a handle.

In a rotating bolt action, you must turn the handle up to unlock it. Then you pull it back to open the breech. After loading, you push it forward and turn it down to lock it. Some people use a straight-pull bolt instead. This design lets you pull the bolt straight back without turning it. This makes the process faster for the shooter.

History shows us many different ways these mechanisms evolved. The Prussian needle gun of 1841 was a single-shot bolt action. Later, Russia introduced the Berdan Type II in 1870. The Mauser Model 1871 was another important metallic-cartridge bolt action. For fast shooting, the M1895 Lee Navy used a straight-pull design.

In modern sports like the biathlon, straight-pull actions are very common. This is because shooting speed is a major part of the race. These different designs show how people have found many ways to make tools work.

In the study of firearms, the term "action" refers to the functional mechanism of a breechloading firearm. This mechanism is responsible for several critical tasks in a specific sequence. It must load the ammunition, lock the breech to contain pressure, fire the cartridge, and finally extract and eject the spent casing.

Without a functioning action, a firearm cannot operate. It is important to distinguish actions from muzzleloaders. Muzzleloaders are single-shot firearms where the powder and projectile are loaded manually through the muzzle. Because the breech is closed off, muzzleloaders use an ignition mechanism called a "lock" rather than an action.

Single-shot actions are the earliest types of cartridge firearm actions. These mechanisms can only hold one round of ammunition at a time. The user must manually reload the firearm after every single shot. One method is the dropping block action, which uses a breechblock to seal the chamber. This can be a pivoting block, which is hinged on a pin and tilts down to expose the chamber. Famous examples include the Peabody and Martini actions.

Another version is the falling block action. In this design, a solid metal breechblock slides vertically within grooves cut into the breech. The Ruger No. 1 and the Sharpes rifle are notable examples of this mechanism.

Other single-shot designs offer different ways to manage the breech. The rolling block action uses a part-cylinder breechblock that rotates around a pivot pin. This design, often associated with Remington firearms in the late 19th century, is known for being rugged and reliable. There is also the hinged block action. This was often used in early military conversions of muzzle-loading muskets. In these designs, the rear portion of the barrel is modified to allow a hinged block to open upward or to the side. For instance, the British Snider–Enfield opened to the side, while the American Allin action hinged forward.

Break action firearms provide a different way to access the breech. In these firearms, the barrel itself is hinged to the receiver. The user "breaks" the gun open to expose the chamber for loading.

These are often used in shotguns. Multi-barrel break actions can be configured as "over-and-under," where barrels sit one above the other. They can also be "side-by-side." Some versions are called "combination guns" if they use both rifle and shotgun barrels. This mechanism allows for very quick and easy reloading of the single chamber.

Repeating actions are more complex because they allow for multiple shots without manual reloading. These actions use a magazine, a cylinder, or a belt to hold extra ammunition. A common repeating mechanism is the revolver. A revolver uses a rotary cylinder to house multiple cartridges. The cylinder indexes each round into alignment with the bore before firing. Some revolvers are "double-action." In these models, the manual pull of the trigger performs two tasks: it rotates the cylinder and cocks the hammer. This allows the shooter to fire many rounds in rapid succession.

Bolt-action firearms are another major category of repeating actions. These rely on a bolt that the user moves manually using a protruding handle.

Most modern bolt actions use a "rotating bolt" or "turn-pull" design. To use this, the shooter must rotate the bolt handle upward to unlock it. Then, they pull the bolt rearward to open the breech and eject the spent cartridge. After loading a new round, the bolt is pushed forward and rotated downward to lock it again. The Mauser system is one of the most widely used rotating bolt designs in history.

To increase the rate of fire, some designers created the straight-pull bolt action. Unlike the rotating bolt, a straight-pull bolt does not require the shooter to rotate the handle to unlock it. The user simply pulls the bolt straight back and pushes it forward. This reduces the required movement from four steps to just two.

This design is very common in the sport of biathlon. Because semi-automatic guns are illegal in biathlon races, athletes rely on the speed of straight-pull actions to remain competitive. This evolution from single-shot to high-speed repeating mechanisms shows the technical progression of firearm design.