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 shotgun is a long-barreled firearm designed to shoot a straight-walled cartridge known as a shotshell, which discharges numerous small spherical projectiles called shot, or a single solid projectile called a slug. Shotguns are most commonly used as smoothbore firearms, meaning that their gun barrels have no rifling on the inner wall, but rifled barrels for shooting sabot slugs are also available.
A semi-automatic rifle is an autoloading rifle that fires a single cartridge with each pull of the trigger and uses part of the fired cartridge's energy to eject the case and load another cartridge into the chamber. In contrast, a bolt-action rifle requires the user to cycle the bolt manually before they can fire a second time, and a fully automatic rifle fires continuously until the trigger is released.
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.
The Pancor Corporation Jackhammer is a 12-gauge, blow-forward gas-operated bullpup automatic shotgun designed in 1984 and patented in 1987. Only three working prototypes of the Jackhammer were built. Nonetheless, its distinctive aesthetics and futuristic design have made it a prop in action films, television programs, and video games.
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 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.
The Benelli M4 is a semi-automatic shotgun produced by Italian firearm manufacturer Benelli Armi SpA, and the fourth and last model of the Benelli Super 90 line of semi-automatic shotguns. The M4 uses a proprietary action design called the "auto-regulating gas-operated" (ARGO) system, which was created specifically for the weapon. Designed in 1998, the M4 was adopted by the armed forces of Italy, the United States, and United Kingdom, among others, and has been used in a variety of conflicts.
An automatic firearm or fully automatic firearm is an autoloading firearm that continuously chambers and fires rounds when the trigger mechanism is actuated. The action of an automatic firearm is capable of harvesting the excess energy released from a previous discharge to feed a new ammunition round into the chamber, and then igniting the propellant and discharging the projectile by delivering a hammer or striker impact on the primer.
A combat shotgun is a shotgun issued by militaries for warfare. The earliest shotguns specifically designed for combat were the trench guns or trench shotguns issued in World War I. While limited in range, the multiple projectiles typically used in a shotgun shell provide increased hit probability unmatched by other small arms.
Pump action is a type of manual firearm action that is operated by moving a sliding handguard on the gun's forestock. When shooting, the sliding forend is pulled rearward to eject any expended cartridge and typically to cock the hammer or striker, and then pushed forward to load a new cartridge into the chamber. Most pump-action firearms use an integral tubular magazine, although some do use detachable box magazines. Pump-action firearms are typically associated with shotguns, although it has been used in rifles, grenade launchers, as well as other types of firearms. A firearm using this operating mechanism is colloquially referred to as a pumpgun.
The Franchi SPAS-12 is a combat shotgun manufactured by Italian firearms company Franchi from 1979 to 2000. The SPAS-12 is a dual-mode shotgun, adjustable for semi-automatic or pump-action operation. The SPAS-12 was sold to military and police users worldwide, as well as on the civilian market.
Rotating bolt is a method of locking the breech of a firearm closed for firing. Johann Nicolaus von Dreyse developed the first rotating bolt firearm, the "Dreyse needle gun", in 1836. The Dreyse locked using the bolt handle rather than lugs on the bolt head like the Mauser M 98 or M16. The first rotating bolt rifle with two lugs on the bolt head was the Lebel Model 1886 rifle. The concept has been implemented on most firearms chambered for high-powered cartridges since the 20th century.
The Benelli M3 is a dual-mode shotgun designed and manufactured by Italian firearms manufacturer Benelli Armi SpA, and the third model of the Benelli Super 90 line of semi-automatic shotguns. The M3 holds a maximum of seven rounds and uses Benelli's proprietary inertia-driven action system first showcased in the M1. The M3 is notable for allowing the user to choose between semi-automatic or pump-action operation.
The Browning Automatic 5, most often Auto-5 or simply A-5, is a recoil-operated semi-automatic shotgun designed by John Browning and manufactured by Fabrique Nationale de Herstal. It was the first successful semi-automatic shotgun design, and remained in production until 1998. The name of the shotgun designates that it is an autoloader with a capacity of five rounds, four in the magazine and one in the chamber. Remington Arms and Savage Arms sold variants called the Remington Model 11 and Savage Model 720 that were nearly identical but lacked the magazine cutoff found on the Browning.
An automatic shotgun is an automatic firearm that fires shotgun shells and uses some of the energy of each shot to automatically cycle the action and load a new round. It will fire repeatedly until the trigger is released or ammunition runs out. Automatic shotguns have a very limited range, but provide tremendous firepower at close range.
A multiple-barrel firearm is any type of firearm with more than one gun barrel, usually to increase the rate of fire or hit probability and to reduce barrel erosion or overheating.
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.
