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.
Mauser, originally the Königlich Württembergische Gewehrfabrik, was a German arms manufacturer. Their line of bolt-action rifles and semi-automatic pistols was produced beginning in the 1870s for the German armed forces. In the late 19th and early 20th centuries, Mauser designs were also exported and licensed to many countries, which adopted them as military and civilian sporting firearms. The Gewehr 98 in particular was widely adopted and copied, and it is the foundation of many of today's sporting bolt-action rifles.
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.
The SUB-2000 is a pistol-caliber carbine manufactured by Kel-Tec CNC Industries of Cocoa, Florida, United States. The rifle is a blowback operated, semi-automatic firearm with its operating spring located in the tubular stock.
The Intratec TEC-9, TEC-DC9, KG-99, and AB-10 are a line of blowback-operated semi-automatic pistols. They were developed by Intratec, an American subsidiary of the Swedish firearms manufacturer Interdynamic AB. Introduced in 1984, the TEC-9 was made of inexpensive molded polymers and a mixture of stamped and milled steel parts. The simple design of the gun made it easy to repair and modify. It was a commercial success, with over 250,000 being sold.
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 also been used in rifles, grenade launchers, and other types of firearms. A firearm using this operating mechanism is colloquially referred to as a pumpgun.
The Ruger 10/22 is a series of semi-automatic rifles produced by American firearm manufacturer Sturm, Ruger & Co., chambered for the .22 Long Rifle rimfire cartridge. It uses a patented 10-round rotary magazine, though higher capacity box magazines are also available. The standard carbine version of the Ruger 10/22 has been in production continuously since 1964, making it one of the most successful rimfire rifle designs in history, with numerous third party manufacturers making parts and accessories for upgrading and customization. The 10/22's aftermarket is so prolific that a complete 10/22 can be built without using any Ruger-made components.
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.
The Ruger Pistol Caliber Carbine is a blowback centerfire semi-automatic pistol-caliber carbine manufactured by Sturm, Ruger & Co., designed as a companion to certain Ruger P series semi-automatic pistols, using the same 9 mm Parabellum and .40 S&W caliber cartridges and magazines of the P-Series pistols.
Kel-Tec CNC Industries Inc., commonly referred to as Kel-Tec, is an American developer and manufacturer of firearms. Founded by George Kellgren in 1991 and based in Cocoa, Florida, the company has manufactured firearms since 1995, starting with semi-automatic pistols and expanding to rifles and then shotguns. Kel-Tec is a privately owned Florida corporation. George Kellgren, Kel-Tec owner and chief engineer, is a Swedish designer who also designed many earlier Husqvarna, Swedish Interdynamics AB, Intratec and Grendel brand firearms. The company has been developing and manufacturing a wide variety of firearms, ranging from semi-automatic handguns, i.e. pistols, to semi-automatic rifles and shotguns.
The Leader T2 MK5 Series firearms were chambered for the 5.56×45mm NATO cartridge and manufactured by Leader Dynamics of Smithfield, NSW, Australia (1978-1982/1983). The Leader was the brainchild of British weapons designer Charles St. George. It was originally a contender for a 5.56 mm Australian military service rifle to replace the then-issued Lithgow L1A1 SLR and Colt M16A1 rifles. What was unique about this endeavor was that Australia had never designed or manufactured its own commercial gas-operated semi-automatic rifle. The rifle was abandoned when the Steyr AUG was adopted for use by the Australian military.
Hi-Point Firearms, also known as Strassell's Machine, Inc, is an American firearms manufacturer based in Mansfield, Ohio. All of their firearms are manufactured in several different locations in Ohio.
SU-16 refers to a series of semi-automatic rifles and carbines manufactured by Kel-Tec CNC Industries, Inc. of Cocoa, Florida, referred to in Kel-Tec's marketing as "Sport Utility rifles". The SU-16 series is notable for its compact, lightweight and simple design; and for being able to be broken down and folded into a compact configuration for transportation and storage. While the barrel, bolt-carrier and mechanism are steel, the SU-16's stock, receiver, and forend are manufactured of high-strength polymer plastic.
The Hi-Point Model C-9 is a polymer-framed, semi-automatic, blowback-operated pistol manufactured by Hi-Point Firearms. It is chambered in 9×19mm Parabellum and is rated to accept +P ammunition. It became well known for its low retail price of under $200. An improved model, the YC9, was originally expected for release by late 2019, but was finally released for sale in August 2023.
The KRISS Vector is a series of weapons based upon the parent submachine gun design developed by the American company KRISS USA, formerly Transformational Defense Industries (TDI).
The Fabarm FP6 is a pump-action combat shotgun that was manufactured by the Italian firearms company Fabbrica Bresciana Armi S.p.A. (FABARM) and sold by Heckler & Koch. It was intended for civilian and law enforcement use.
The Intratec TEC-22 is a semi-automatic handgun chambered in .22 Long Rifle. It was also marketed as the Scorpion and Sport-22. The TEC-22 operates using a straight blow-back action.
United States 
