Glossary of Firearms Terms - C

C

• caliber/calibre: 1. In small arms, the internal diameter of a firearm's barrel or a cartridge's bullet, usually expressed in millimeters or hundredths of an inch; in measuring rifled barrels this may be measured across the lands (such as .303 British) or grooves (such as .308 Winchester). 2. A specific cartridge for which a firearm is chambered, such as .44 Magnum. 3. In artillery, the length of the barrel expressed in terms of the internal diameter; for example, a 3 inch, 30 caliber gun would have a barrel 3 inches in internal diameter and 90 (30 times 3) inches in length.

• carbine: 1. A shortened version of a service rifle, often chambered in a less potent cartridge. The M4 Carbine is an example which uses the same cartridge but a shorter barrel, whereas the M1 Carbine is an example using a different cartridge. 2. A shortened version of the infantryman's musket or rifle suited for use by cavalry.

• cartridge: The assembly consisting of a bullet, gunpowder, shell casing, and primer. When counting, it is referred to as a round.

• caseless ammunition: a type of small arms ammunition that eliminates the cartridge case that typically holds the primer, propellant, and projectile together as a unit.

• Casket magazine: a quad stack box magazine.

• centerfire: A cartridge in which the primer is located in the center of the cartridge case head. Unlike rimfire cartridges, the primer is a separate and replaceable component. The centerfire cartridge has replaced the rimfire in all but the smallest cartridge sizes. Except for low-powered .22 and .17 caliber cartridges, and a handful of antiques, all modern pistol, rifle, and shotgun ammunition are centerfire.

• chain gun: type of machine gun or autocannon that uses an external source of power to cycle the weapon.

• chamber: The portion of the barrel or firing cylinder in which the cartridge is inserted prior to being fired. Rifles and pistols generally have a single chamber in their barrels, while revolvers have multiple chambers in their cylinders and no chamber in their barrel.

• chambering: Inserting a round into the chamber, either manually or through the action of the weapon (e.g., pump-action, lever-action, bolt-action, or automatic-action.).

• charger: A speedloader that holds several cartridges together in a single unit for easier loading of a firearm's magazine. A stripper clip is used only for loading the magazine and is not necessary for the firearm to function.

• charging handle: device on a firearm which, when operated, results in the hammer or striker being cocked or moved to the ready position.

• clip: A device that is used to store multiple rounds of ammunition together as a unit, ready for insertion into the magazine of a repeating firearm. This speeds up the process of loading and reloading the firearm as several rounds can be loaded at once, rather than one round being loaded at a time. The term clip commonly refers to a firearm magazine, though this usage is incorrect. In the correct usage, a clip is used to feed a magazine or revolving cylinder, while a magazine or a belt is used to load cartridges into the chamber of a firearm.

• collateral damage: Damage that is unintended or incidental to the intended outcome. The term originated in the United States military, but it has since expanded into broader use.

• collimator sight: A type of optical "blind" sight that allows the user looking into it to see an illuminated aiming point aligned with the device the sight is attached to regardless of eye position (parallax free). The user can not see through the sight so it is used with both eyes open while one looks into the sight, with one eye open and moving the head to alternately see the sight and then at the target, or using one eye to partially see the sight and target at the same time. (variant names/types: collimating sight, occluded eye gunsight (OEG).)

• combination gun: A shoulder-held firearm that has two barrels; one rifle barrel and one shotgun barrel. Most combination guns are of an over/under design (abbreviated as O/U), in which the two barrels are stacked vertically on top of each other, but some combination guns are of a side-by-side design (abbreviated as SxS), in which the two barrels sit beside each other.

• cordite: A family of smokeless propellants developed and produced in the United Kingdom from 1889 to replace gunpowder as a military propellant. Like gunpowder, cordite is classified as a low explosive because of its slow burning rates and consequently low brisance. The hot gases produced by burning gunpowder or cordite generate sufficient pressure to propel a bullet or shell to its target, but not enough to destroy the barrel of the firearm, or gun.

• CQB: Close quarters combat (CQC) or close quarters battle (CQB) is a type of fighting in which small units engage the enemy with personal weapons at very short range, potentially to the point of hand-to-hand combat or fighting with hand weapons such as swords or knives.

• cylindro-conoidal bullet: A hollow base bullet, shaped so that, when fired, the bullet will expand and seal the bore. It was invented by Captain John Norton of the British 34th Regiment in 1832, after he examined the blow pipe arrows used by the natives in India and found that their base was formed of elastic locus pith, which by its expansion against the inner surface of the blow pipe prevented the escape of air past it.