In firearms terminology, an action is the functional mechanism of a breechloading 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 pistol is a repeating handgun that automatically ejects and loads cartridges in its chamber after every shot fired, but only one round of ammunition is fired each time the trigger is pulled. The pistol's fire control group disconnects the trigger mechanism from the firing pin/striker until the trigger has been released and reset manually, unlike the self-cycled firing mechanism in fully automatic pistols.
The Makarov pistol or PM is a Soviet semi-automatic pistol. Under the project leadership of Nikolay Fyodorovich Makarov, it became the Soviet Union's standard military and Militsiya side arm in 1951.
The Desert Eagle or simply Deagle is a single-action, gas-operated, semi-automatic pistol capable of chambering the .50 Action Express, the largest centerfire cartridge of any magazine-fed, self-loading pistol and famous for other large caliber chamberings.
The SIG Sauer P220 is a semi-automatic pistol designed in 1975 by the SIG Arms AG division of Schweizerische Industrie Gesellschaft, and produced by J. P. Sauer & Sohn, in Eckernförde. It is currently manufactured by both SIG Sauer companies: SIG Sauer GMBH, of Eckernförde, Germany; and SIG Sauer, Inc., of New Hampshire, United States.
The M1901 Mannlicher Self-Loading, Semi-Automatic Pistol was an early semi-automatic pistol design. The Bundeswehr Museum of German Defense Technology in Koblenz has one of these specimen in its collection.
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 Mannlicher M1894 was an early blow-forward semi-automatic pistol.
The Mateba Model 6 Unica is a recoil operated semi-automatic revolver, one of only a few of this type ever produced. It was developed by Mateba, based in Pavia, Italy. Inventor Emilio Ghisoni (1937–2008), who was also famous for later designing the Chiappa Rhino, is listed as the owner of U.S. patent 4,712,466 which details the operation of the weapon.
The USP is a semi-automatic pistol developed in Germany by Heckler & Koch GmbH (H&K) as a replacement for the P7 series of handguns.
The Walther P5 is a 9mm semi-automatic pistol developed in the mid-1970s by the German small arms manufacturer Carl Walther GmbH Sportwaffen. It was designed with the German police forces in mind, who sought to replace existing 7.65mm pistols with a modern service sidearm incorporating enhanced safety features and chambered in 9×19mm Parabellum. A subsequent bid resulted in the Walther P5 being introduced into service alongside the SIG Sauer P225 and Heckler & Koch P7.
The K100 is a 9×19mm semi-automatic pistol designed and built by Grand Power s.r.o. in Slovenská Ľupča, Slovakia located approximately 11 kilometers east of Banská Bystrica, Slovakia which is the region's major city.
The Beretta Px4 Storm is a semi-automatic pistol intended for personal defense and law enforcement use. It is available in full size, Compact, and Subcompact versions. The Px4 uses a trigger and safety system similar to the Beretta 92 and the Beretta 8000 series, though it is distinguished from its predecessors by its light-weight polymer construction with steel inserts, standard Picatinny rail, and swappable grip backstraps. The full size and Compact versions use the same short-recoil, rotating barrel action as the Beretta 8000 series, whereas the Subcompact uses the tilt barrel system.
The Beretta 8000 (Cougar) is a family of rotating barrel semi-automatic pistols that were designed and manufactured by Beretta of Italy.
The Wildey is a gas-operated, double- or single-action pistol designed by Wildey J. Moore. It was designed to fire several high-pressure proprietary cartridges including the .45 Winchester Magnum and the .475 Wildey Magnum. They are currently being produced by USA Firearms Corp.-Wildey Guns of Winsted, Connecticut.
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.
The Grizzly Win Mag pistols were conceived, invented, designed, engineered and developed in the 1980s by the sole inventor, Perry Arnett, who licensed his patent for an interchangeable caliber semi-automatic pistol to L.A.R. Manufacturing Inc. Perry Arnett's designs were initially flawed and were improved upon by Heinz Augat. The L.A.R. Grizzly was one of the most powerful semi-automatic pistol ever commercially produced, after the Mateba Unica 6.
The OTs-33 Pernach is a Russian 9x18 Makarov machine pistol, derived from the 5.45 mm OTs-23 Drotik machine pistol. The Pernach is an automatic pistol designed to replace the Stechkin APS in various special OMON units within the Russian police, the Russian Ministry of Internal Affairs (MVD) and other paramilitary units. The OTs-33 was developed in 1995 by Igor Stechkin at the TsKIB SOO design bureau, and it went into limited production at the KBP Instrument Design Bureau. It is also known as the SBZ-2, derived from the names of the KBP team responsible for the pistol, namely Stechkin, Baltser (Бальцер) and Zinchenko (Зинченко).
The CZ 110 is a lightweight Czech 9 mm semi-automatic pistol developed and produced by Česká Zbrojovka of Uherský Brod. The CZ 110 is a double-action (DA) variant of the CZ 100.
The SIG Sauer system is a type of action found in self-loading handguns. It is a refinement of designs based on the work of both John M. Browning and Charles Petter which began with the Colt Model 1900, progressed to the French Model 1935A, and later the SIG P210 handgun. This action first appeared in the United States on the Browning BDA .45 ACP caliber handgun around 1975. It represents a design which optimizes the cost of production of handguns while instilling high levels of accuracy and dependability. It is the basis for several SIG Sauer, Inc. designs which have been widely adopted for police, military, and civilian use and is the action used in the M17 and M18 sidearms of the United States Armed Forces. It has become a highly copied design found in many parts of the world today.
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