A firearm is any type of gun that uses an explosive charge and is designed to be readily carried and operated by an individual. The term is legally defined further in different countries.
A machine pistol is a handgun that is capable of fully automatic fire, including stockless handgun-style submachine guns.
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.
The Colt AR-15 is a lightweight, magazine-fed, gas-operated, autoloading rifle manufactured by Colt's Manufacturing Company ("Colt"). The rifle is a derivative of its predecessor, the ArmaLite AR-15, an automatic rifle designed by Eugene Stoner and other engineers at ArmaLite in 1956.
In the United States, assault weapon is a controversial term applied to different kinds of firearms. There is no clear, consistent definition. It can include semi-automatic firearms with a detachable magazine, a pistol grip, and sometimes other features, such as a vertical forward grip, flash suppressor, or barrel shroud. Certain firearms are specified by name in some laws that restrict assault weapons. When the now-defunct Federal Assault Weapons Ban was passed in 1994, the U.S. Department of Justice said, "In general, assault weapons are semiautomatic firearms with a large magazine of ammunition that were designed and configured for rapid fire and combat use." The commonly used definitions of assault weapons are under frequent debate, and have changed over time.
The StG 44 is a German assault rifle developed during World War II by Hugo Schmeisser. It is also known by its early designations as the MP 43 and MP 44. The StG 44 was an improvement of an earlier design, the Maschinenkarabiner 42(H).
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, and 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.
An automatic firearm or fully automatic firearm is a self-loading 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.
Selective fire, or select fire, is the capability of a weapon to be adjusted to fire in semi-automatic, fully automatic, and/or burst mode. The modes are chosen by means of a selector switch, which varies depending on the weapon's design. Some selective-fire weapons have burst fire mechanisms to limit the maximum number of shots fired automatically in this mode. The most common limits are two or three rounds per trigger pull. Fully automatic fire refers to the ability for a weapon to fire continuously until either the feeding mechanism is emptied or the trigger is released. Semi-automatic refers to the ability to fire one round per trigger pull.
A firearm is said to fire from an open bolt or open breech if, when ready to fire, the bolt and working parts are held to the rear of the receiver, with no round in the chamber. When the trigger is actuated, the bolt travels forward, feeds a cartridge from the magazine or belt into the chamber, and fires that cartridge in the same movement. Like any other self-loading design, the action is cycled by the energy released from the propellant, which sends the bolt back to the rear, compressing the mainspring in readiness for firing the next round. In an open-bolt gun firing semi-automatically, the bolt is caught and held at this point by the sear after each shot; and in automatic open-bolt fire, it's caught and held in this manner whenever the trigger is released. In contrast to this, in closed-bolt guns, the trigger and sear do not affect the movement of the bolt directly.
Rate of fire is the frequency at which a specific weapon can fire or launch its projectiles. This can be influenced by several factors, including operator training level, mechanical limitations, ammunition availability, and weapon condition. In modern weaponry, it is usually measured in rounds per minute or rounds per second.
A stripper clip is a speedloader that holds several cartridges together in a single unit for easier and faster loading of a firearm magazine.
A self-loading rifle or autoloading rifle is a rifle with an action using a portion of the energy of each cartridge fired to load another cartridge. Self-loading pistols are similar, but intended to be held and fired by a single hand, while rifles are designed to be held with both hands and fired from the shoulder.
A trigger is a mechanism that actuates the function of a ranged weapon such as a firearm, airgun, crossbow, or speargun. The word may also be used to describe a switch that initiates the operation of other non-shooting devices such as a trap, a power tool, or a quick release. A small amount of energy applied to the trigger leads to the release of much more energy.
Muzzle rise, muzzle flip or muzzle climb refers to the tendency of a firearm's or airgun's muzzle to rise up after firing. It more specifically refers to the seemingly unpredictable "jump" of the firearm's muzzle, caused by combined recoil from multiple shots being fired in quick succession. It has an adverse effect on maintaining accuracy with using automatic weapons or rapid-firing semi-automatic firearms, as a moving muzzle can throw off the shooter's aim, causing subsequent shots to miss the intended target.
A rifle cartridge is a firearm cartridge primarily designed and intended for use in a rifle/carbine, or machine gun.
In firearms, a safety or safety catch is a mechanism used to help prevent the accidental discharge of a firearm, helping to ensure safer handling.
An AR-15–style rifle is a lightweight semi-automatic rifle based on or similar to the Colt AR-15 design. The Colt model removed the selective fire feature of its predecessor, the original ArmaLite AR-15, which is a scaled-down derivative of the AR-10 design. It is closely related to the military M16 rifle.
