Lesson 1. PISTOL: TYPES, PARTS and OPERATION

Pistol: A gun that has short barrel and can be held, aimed, and fired with one hand.

The two most common types of pistols in use today are the Revolver and the Semi-Automatic.

A pistol consists of three major components: The frame, the barrel, and the action. Although both revolvers and semi-automatics have these three components, some of the parts within these components and the ways in which they function are different.

REVOLVERS

A revolver is a pistol that has a rotating cylinder designed to contain cartridges. The action of the trigger and hammer will rotate the cylinder and fire a cartridge.

The frame of the revolver is the backbone to which all other parts are attached.

The barrel is the metal tube through which a bullet passes on its way to a target. The inside of the barrel is called the bore.

The bore has spiral grooves cut into it. The ridges of metal between these grooves are called lands. The distance between the lands determines the caliber of the pistol. Together, the grooves and lands make up what is known as rifling. The rifling make the bullets fly more stable and more accurate. The front end of the barrel where the bullet exists is called the muzzle. The front sight is located on top of the barrel near the muzzle, and together with the rear sight is used to aim the pistol. The trigger guard is located on the underside of the frame and is designed to protect the trigger in order to reduce the possibility of an unintentional firing.

The action is a group of moving parts used to load, fire, and unload the pistol. The trigger is located on he underside of the frame. The hammer is attached to the rear of the frame. When the trigger is pulled, it activates the hammer which in turn causes the firing pin to strike and fire the cartridge.

In Single-action revolvers, the trigger performs only one action: releasing the hammer. The trigger does not cock the hammer. The hammer must be manually cocked in order to fire the gun.

There are two types of revolver actions: single-action, and double-action.

In Double-action revolvers, the trigger performs two tasks: Cocking and releasing the hammer. Most of the double-action revolvers can also be fired in a single-action mode by manually cocking the hammer.

The cylinder holds cartridges in individual chambers which are arranged in a circular pattern. Each time that the hammer moves to the rear, the cylinder turns and brings a new chamber in line with the barrel and the firing pin. The cylinder release latch releases the cylinder and allows it to swing out so that cartridges can be loaded and unloaded.

Most revolvers have an ejector also know as an extractor, and an ejector rod. The purpose of the ejector is to remove cartridges and empty cases from the cylinder.

SEMI-AUTOMATICS

A semi-automatic pistol differs significantly from a revolver in its basic operation. After a cartridge is fired by pulling the trigger, the empty case is automatically extracted and ejected, and a new cartridge is inserted into the chamber. Because a new cartridge is automatically loaded into the chamber, this type of pistol is sometimes referred to as an autoloader.

The frame of a semi-automatic pistol, like that of a revolver, is the backbone to which all other parts are attached.

The safety is located on the semi-automatic’s frame of slide. The safety is a mechanical device designed to reduce the chance of an accidental discharge. Since safeties, like all mechanical devices, can malfunction, the prevention of an accident is ultimately the responsibility of the individual who is handling the pistol. Revolvers do not usually have safeties. The slide stops also known as slide release is designed to hold the slide of the pistol to the rear. Some semi-automatics also have a part known as a decocking lever, which is used to lower the hammer and uncock the pistol. The trigger guard is located on the underside of the frame and is designed to protect the trigger in order to reduce the possibility of an unintentional firing.

The magazine is a storage device designed to hold cartridges ready for insertion into the chamber. The magazine release is a button; lever or a switch that releases the magazine so that is can be removed from the pistol.

The barrel on a semi-automatic pistol is basically the same as the barrel on a revolver with one major exception: at the rear of the barrel on a semi-automatic is a single chamber which will contain the cartridge at the instant of firing. In contrast, the revolver has multiple chambers which are located in the rotating cylinder.

Because of the large number of different mechanical designs for semi-automatics, the actions can vary greatly. Some semi-automatics have a hammer, and there are models which do not have a visible hammer are commonly referred to as hammerless or double-action only. All semi-automatics have a slide. In most semi-automatics, the first cartridge must always be manually cycled into the firing chamber by retraction the slide and then releasing it. As the slide returns to the closed position, it removes a cartridge from the top of the magazine and inserts it into the chamber.

The front sight and rear sight are usually located on the top of the slide. The trigger is located on the underside of the frame. When the trigger is pulled, it activates the hammer or the internal firing mechanism which, when released causes the firing pin to strike and fire the cartridge. When a semi-automatic is fired, the slide moves to the rear, ejecting the empty cartridge case and usually cocking the pistol in the process. When the slide moves forward, it picks up and pushes the top cartridge in the magazine into the chamber.

There are three types of semi-automatic actions: single-action, double/single-action, and double-action-only (DAO).

In a single-action semi-automatic, the trigger performs a single task: releasing the hammer.

In a double/single action semi-automatic, the trigger performs two tasks: cocking the hammer for the first shot, and releasing the hammer. After the first shot is fired, the movement of the slide will cock the hammer for all successive shots, and the trigger will only performs single action task.

n a double-action-only semi-automatic, the trigger will cock and release the hammer on the first shot and all successive shots. The movement of the slide will not cock the hammer. The double-action-only pistols (even with a hammer) can not be manually cocked to a single-action mode.