The chamber of a firearm is the cavity at the back end of a breechloading weapon's barrel or cylinder, where the ammunition is inserted before being fired. The rear opening of the chamber is the breech, and is sealed by the breechblock or the bolt. [1] [2]
The act of chambering a cartridge means the insertion of a round into the chamber, either manually or through the action of the weapon, e.g., pump-action, lever-action, bolt action, or autoloading operation generally in anticipation of firing the weapon, without need to "load" the weapon upon decision to use it (reducing the number of actions needed to discharge). [3]
Automatic and single-shot pistols (such as Derringers), rifles, and shotguns generally have a single chamber integral to their barrels, but revolvers have multiple chambers in their cylinder, and no chamber in their barrel. Thus, pistols, rifles, and shotguns can usually still be fired with the magazine removed as long as a cartridge is inserted into the chamber, while a revolver cannot be fired at all with its cylinder swung out or broken open.[ citation needed ]
In firearms design or modification, "chambering" is fitting a weapon's chamber for a particular caliber or round, [4] so a Colt Model 1911 is chambered for .45 ACP or .38 Super, or re-chambered for .38/.45 Clerke. While the majority of firearms are chambered for one caliber, some are chambered for multiple calibers; however firing an oversized or undersized cartridge can be hazardous. [2]
The chamber is a key component to the practice of forensic firearm examination. The chamber is known to imprint its surface striations irregularities on the cartridge case, in what are called chamber marks, due to the pressure produced when shooting. [5] [6] [7] Such imperfections in chamber may be produced in the manufacturing process or through extensive use. [8] Such chamber marks are more pronounced on substandard firearms or when firing from an undersized chamber. [5]
In recent years there has been a push to automate this process via the use of automated firearms databases. [9] Ballistics identification has also seen the development of microstamping technology which purposefully creates chamber marks through engravings on the firing pin and breech face. [10]
A firearm is any type of gun that uses an explosive charge and is designed to be readily carried and used by an individual. The term is legally defined further in different countries.
A revolver is a repeating handgun that has at least one barrel and uses a revolving cylinder containing multiple chambers for firing. Because most revolver models hold up to six cartridges, before needing to be reloaded, revolvers are commonly called six shooters.
In firearm designs, the term single-shot refers to guns that can hold only a single round of ammunition inside and thus must be reloaded manually after every shot. Compared to multi-shot repeating firearms ("repeaters"), single-shot designs have no moving parts other than the trigger, hammer/firing pin or frizzen, and therefore do not need a sizable receiver behind the barrel to accommodate a moving action, making them far less complex and more robust than revolvers or magazine/belt-fed firearms, but also with much slower rates of fire.
A cartridge, also known as a round, is a type of pre-assembled firearm ammunition packaging a projectile, a propellant substance and an ignition device (primer) within a metallic, paper, or plastic case that is precisely made to fit within the barrel chamber of a breechloading gun, for convenient transportation and handling during shooting. Although in popular usage the term "bullet" is often used to refer to a complete cartridge, the correct usage only refers to the projectile.
In firearms terminology, an action is the functional mechanism of a breech-loading firearm that handles the ammunition cartridges, or the method by which that mechanism works. Actions are technically not present on muzzleloaders, as all those are single-shot firearms with a closed off breech with the powder and projectile manually loaded from the muzzle. Instead, the muzzleloader ignition mechanism is referred to as the lock.
A semi-automatic firearm, also called a self-loading or autoloading firearm, is a repeating firearm whose action mechanism automatically loads a following round of cartridge into the chamber and prepares it for subsequent firing, but requires the shooter to manually actuate the trigger in order to discharge each shot. Typically, this involves the weapon's action utilizing the excess energy released during the preceding shot to unlock and move the bolt, extracting and ejecting the spent cartridge case from the chamber, re-cocking the firing mechanism, and loading a new cartridge into the firing chamber, all without input from the user. To fire again, however, the user must actively release the trigger, allow it to "reset", before pulling the trigger again to fire off the next round. As a result, each trigger pull only discharges a single round from a semi-automatic weapon, as opposed to a fully automatic weapon, which will shoot continuously as long as the ammunition is replete and the trigger is kept depressed.
A semi-automatic pistol is a handgun that automatically ejects and loads cartridges in its chamber after every shot fired. Only one round of ammunition is fired each time the trigger is pulled, as the pistol's fire control group disconnects the trigger mechanism from the firing pin/striker until the trigger has been released and reset.
A repeating rifle is a single-barreled rifle capable of repeated discharges between each ammunition reload. This is typically achieved by having multiple cartridges stored in a magazine and then fed individually into the chamber by a reciprocating bolt, via either a manual or automatic action mechanism, while the act of chambering the round typically also recocks the hammer/striker for the following shot. In common usage, the term "repeating rifle" most often refers specifically to manual repeating rifles, as opposed to self-loading rifles, which use the recoil, gas, or blowback of the previous shot to cycle the action and load the next round, even though all self-loading firearms are technically a subcategory of repeating firearms.
A lever action is a type of action for repeating firearms that uses a manually operated cocking handle located around the trigger guard area that pivots forward to move the bolt via internal linkages, which will feed and extract cartridges into and out of the chamber, and cock the firing pin mechanism. This contrasts to other type of repeating actions such as the bolt-action, pump-action, semi-automatic, fully automatic, and/or burst mode actions. A firearm using this operating mechanism is colloquially referred to as a levergun.
A gun barrel is a crucial part of gun-type weapons such as small firearms, artillery pieces, and air guns. It is the straight shooting tube, usually made of rigid high-strength metal, through which a contained rapid expansion of high-pressure gas(es) is used to propel a projectile out of the front end (muzzle) at a high velocity. The hollow interior of the barrel is called the bore, and the diameter of the bore is called its caliber, usually measured in inches or millimetres.
A breechblock is the part of the firearm action that closes the breech of a breech loading weapon before or at the moment of firing. It seals the breech and contains the pressure generated by the ignited propellant. Retracting the breechblock allows the chamber to be loaded with a cartridge.
A rim is an external flange that is machined, cast, molded, stamped, or pressed around the bottom of a firearms cartridge. Thus, rimmed cartridges are sometimes called "flanged" cartridges. Almost all cartridges feature an extractor or headspacing rim, in spite of the fact that some cartridges are known as "rimless cartridges". The rim may serve a number of purposes, including providing a lip for the extractor to engage, and sometimes serving to headspace the cartridge.
H&R 1871, LLC, or more commonly known as Harrington & Richardson, is an American brand of firearms and a subsidiary of JJE Capital Holdings. H&R ceased independent production February 27, 2015.
In breechloading firearms, an extractor is an action component that serves to remove spent casings of previously fired cartridges from the chamber, in order to vacate the chamber for loading a fresh round of ammunition.
Break action is a type of firearm action in which the barrel(s) are hinged much like a door and rotate perpendicularly to the bore axis to expose the breech and allow loading and unloading of cartridges. A separate operation may be required for the cocking of a hammer to fire the new round. There are many types of break-action firearms; break actions are universal in double-barreled shotguns, double-barreled rifles, combination guns, and are commonly found in single shot pistols, rifles, shotguns, including flare guns, grenade launchers, air guns, and some older revolver designs. They are also known as hinge-action, break-open, break-barrel, break-top, or, on old revolvers, top-break actions.
An antique firearm is a term used to describe a firearm that was designed and manufactured prior to the beginning of the 20th century. Although the exact definition of what constitutes an "antique firearm" varies between countries, the advent of smokeless powder or the start of the Boer War are often used as cut-off dates. Antique firearms are usually collected because of their historical interest and/or their monetary value.
The following are terms related to firearms and ammunition topics.
Chiappa Firearms, Armi Sport di Chiappa, is an Italian firearms manufacturing company based in Brescia. It was founded in 1958 by Ezechiele Chiappa as Armi Sport. Total unit production is around 60,000 per year. Its U.S. headquarters are in Dayton, Ohio.
Recoil operation is an operating mechanism used to implement locked-breech autoloading firearms. Recoil operated firearms use the energy of recoil to cycle the action, as opposed to gas operation or blowback operation using the pressure of the propellant gas.
A repeating firearm or repeater is any firearm that is capable of being fired repeatedly before having to manually reloaded with new ammunition into the weapon.