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Roller Locked
In firearms operating systems, the term roller locked refers to locking the bolt with Rolling-element bearing, rollers. Notable examples of firearms using this method are the MG 42 general-purpose machine gun, and the CZ 52 semi-automatic pistol. It was also applied in the experimental Gewehr 43#Gerät 03 prototype, ''Gerät 03'' semi-automatic rifle and ''Gerät 06'' and EM-2 rifle#Background, EM-1 experimental assault rifles. The MG 42's lineage continued past World War II, forming the basis for the nearly identical MG1 (MG 42/59), chambered in 7.62×51mm NATO, which subsequently evolved into the MG1A3, and later the Bundeswehr's Rheinmetall MG 3, MG 3, Italian MG 42/59 and Austrian MG 74. It also spawned the Yugoslav unlicensed nearly identical Zastava M53. History Origin of the roller-locking is debated: even though the general principle of utilizing "ball bearing parts" under radial pressure "for preventing uncoupling of the coupling members" was known no later than 1910s, it ...
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Rolling-element Bearing
In mechanical engineering, a rolling-element bearing, also known as a rolling bearing, is a bearing which carries a load by placing rolling elements (such as balls or rollers) between two concentric, grooved rings called races. The relative motion of the races causes the rolling elements to roll with very little rolling resistance and with little sliding. One of the earliest and best-known rolling-element bearings are sets of logs laid on the ground with a large stone block on top. As the stone is pulled, the logs roll along the ground with little sliding friction. As each log comes out the back, it is moved to the front where the block then rolls on to it. It is possible to imitate such a bearing by placing several pens or pencils on a table and placing an item on top of them. See " bearings" for more on the historical development of bearings. A rolling element rotary bearing uses a shaft in a much larger hole, and cylinders called "rollers" tightly fill the space between t ...
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Flapper Locking
Flapper locking is a type of locking mechanism used in self-loading firearms. It involves a pair of flappers on the sides of the bolt that each lock into an outwards recess in the receiver as the bolt is in battery. As the bolt is forced backwards after the firing of a cartridge, the flappers recede back into the bolt, therefore unlocking and sending the bolt backwards to cycle the gun. The design was patented in 1870 by Lieutenant Friberg of the Swedish Army, but the first actual example of a firearm that used this was made by another Swedish man named Kjellman in 1907. Most use of flapper locking came from the designs of the Soviet Union's Vasily Degtyaryov in the years surrounding World War II. Examples *Gewehr 41 (Walther) *Gewehr 43 *Degtyaryov machine gun *RPD machine gun *DShK *EM-2 rifle *AVS-36; used as secondary locking *MG 51 *Mauser 1906/08 pistol and 1905/06 rifle See also *Roller locked (similar) *Rotating bolt *Bolt action Bolt-action is a type of manual ...
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Rotating Bolt
Rotating bolt is a method of locking the breech (or rear barrel) 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. Design Ferdinand Ritter von Mannlicher, who had earlier developed a non-rotating bolt straight-pull rifle, developed the Steyr-Mannlicher M1895, a straight-pull rifle with a rotating bolt, which was issued to the Austro-Hungarian Army. Mannlicher then developed the M1893 auto rifle which had a screw delayed bolt and later the Mannlicher M1900 operated by a gas piston. This was an inspiration for later gas operated, semi-automatic and selective fire firearms (such as the M1 ...
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Collet
A collet is a segmented sleeve, band or ''collar''. One of the two radial surfaces of a collet is usually tapered (i.e a truncated cone) and the other is cylindrical. The term ''collet'' commonly refers to a type of chuck that uses collets to hold either a workpiece or a tool (such as a drill) but has other mechanical applications. An external collet is a sleeve with a cylindrical inner surface and a conical outer surface. The collet can be squeezed against a matching taper such that its inner surface contracts to a slightly smaller diameter, squeezing the tool or workpiece to hold it securely. Most often the collet is made of spring steel, with one or more kerf cuts along its length to allow it to expand and contract. This type of collet holds the external surface of the tool or workpiece being clamped. This is the most usual type of collet chuck. An external collet clamps against the internal surface or bore of a hollow cylinder. The collet's taper is internal and the ...
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Thompson Submachine Gun
The Thompson submachine gun (also known as the "Tommy Gun", "Chicago Typewriter", "Chicago Piano", “Trench Sweeper” or "Trench Broom") is a blowback-operated, air-cooled, magazine-fed selective-fire submachine gun, invented by United States Army Brigadier general John T. Thompson in 1918. It was originally designed to break the stalemate of trench warfare of World War I, but was not finished until after the war ended. The Thompson saw early use by the United States Marine Corps during the Banana Wars, the United States Postal Inspection Service, the Irish Republican Army, the Republic of China, and the FBI (following the Kansas City Massacre). The weapon was also sold to the general public. Because it could be obtained so easily, the Thompson became notorious during the Prohibition era as the signature weapon of various organized crime syndicates in the United States in the 1920s. It was a common sight in the media at the time, and was used by both law enforcement office ...
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Blaser R93 Tactical
The Blaser R93 Tactical is a German bolt action sniper rifle, based on the Blaser R93 design. It has as variants the Blaser LRS 2 and Tactical 2. It is used by German and Dutch police forces as well as the Australian military and special police units. The rifles were manufactured by the German firearms manufacturer Blaser. Design The LRT (Long Range Tactical), LRS 2 (Long Range Sporter 2) and Tactical 2 rifles are straight-pull bolt-action take down sniper rifles. The straight-pull action design was introduced in the Blaser R93 hunting rifle line. These actions allows for faster follow-up shots compared to traditional turn bolt actions. The rifles are designed to fire small groups (sub 0.07 mrad (7 mm at 100 m; 0.25 moa) with factory match ammunition. The LRS 2 version, comes chambered in .223 Remington, 6mm Norma BR, 6.5×55mm, .308 Winchester and .300 Winchester Magnum. An uncommon part of its design is that it is a straight-pull bolt-action rather than a turn-bolt, ...
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Blaser R93
The Blaser R93 is a straight-pull action precision rifle offered in a multitude of calibers and barrel lengths manufactured by the German  firearms manufacturer Blaser. Designed by Blasers' designer Mr. Meinhard Zeh in 1993, it had a number of features rare on modern hunting rifles, including a manual cocking system and a proprietary Blaser saddle scope mount for mounting the optic directly to the quick-change barrel In 2002, more than 100,000 complete Blaser R93 rifles had been produced. By 2017, more than 200,000 R93 rifles had been produced, but it is not clear whether the R93 Tactical variant is included in these numbers. History The predecessor of the R93 was the 60 degree turn bolt action Blaser R84, which was discontinued after the introduction of the R93 in 1993. The successor of R93, Blaser R8, was introduced in 2008. Production of the R93 ended around 2016/2017. Design features Modularity The Blaser R93 is a truly modular system built around an alumin ...
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Blaser R8
The Blaser R8 is a German straight-pull rifle known for its radially locking bolt system, modularity and its barrel mounted scope mount manufactured by Blaser. The rifle also features a manual cocking system and a direct trigger. In 2015 there had been produced more than complete Blaser R8 rifles. It is based on the Blaser R93 rifle series that was discontinued in 2016. Design features Modularity The Blaser R8 is a truly modular system built around an aluminium alloy receiver frame, offering differing stocks and barrels of varying length and thickness. Optionally a steel receiver frame can be ordered that increases the weight by approximately . The R8 is available in calibers from .204 Ruger to .500 Jeffery. Different bolt heads for different groups of calibers are user changeable and the barrel has a quick-change design which lets the user switch barrels using two screws and a hex key, making the Blaser R8 a modular firearm. For affordable training a .22 Long Rifle conver ...
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Savage Arms
Savage Arms is an American gunmaker based in Westfield, Massachusetts, with operations in Canada. Savage makes a variety of rimfire and centerfire rifles, as well as Stevens single-shot rifles and shotguns. The company is best known for the Model 99 lever-action rifle, no longer in production, and the .300 Savage. Savage was a subsidiary of Vista Outdoor until 2019 when it was spun off. History Savage Arms was founded in 1894 by Arthur Savage in Utica, New York. Within 20 years they were producing rifles, handguns, and ammunition. Savage introduced the first hammerless lever-action rifle, the Model 1895, derived from Arthur Savage's Model 1892 rifle that he had designed for Colt in a failed bid for a US Army rifle contract that instead was won by the Krag–Jørgensen design. The Model 1895 won a New York National Guard contract, but the contract was cancelled due to political controversy. Savage was one of six companies to participate in the United States Army trials f ...
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Heym SR 30
The Heym SR 30 is a straight-pull rifle produced in Germany by Heym. The rifle is also available in a left hand version. Locking mechanism The mechanism uses 6 ball bearings symmetrically positioned around the circumference of the bolt head as locking elements. When the bolt handle is pushed forward, it forces a central plunger down the interior of the bolt body, forcing the diameter ball bearings out to lock into a negative recess in the receiver. There are not six matching negative shaped (concave) recesses in the receiver. That would be very hard to practically produce at the required precision level. Instead there is a simple continuous groove machined for the six ball bearings to lock into. The continuous semi-round groove in conjuncion with the barrel positions the bolt to the front and back and regulates a practically achievable headspace during production. The lockup strengthens with increased chamber pressure. The plunger retracts when the bolt handle is pulled ...
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Anschütz 1827 Fortner
Anschütz 1827 Fortner is a straight pull rifles, straight-pull action biathlon rifle designed by Peter Fortner junior and produced in cooperation with J. G. Anschütz. The rifle has been dominant in the sport of biathlon since the late 1980s, and is the current sport standard. It is estimated to be used by 97% of biathlon competitors worldwide. About 7000 had been manufactured by 2007. History Anschütz has been producing biathlon rifles since 1976. The design of the 1827 Fortner action dates back to 1984, when Peter Fortner was having beers with Peter Angerer from West Germany who recently had taken the individual biathlon gold at the Biathlon at the 1984 Winter Olympics, 1984 Winter Olympics. Angerer expressed that he wanted a rifle which could match those used by Soviet and East German competitors. Fortner took the challenge and within a few months developed and patented what was to become known as the "Fortner action", with the 1827 Fortner introduced around 1984. The Fo ...
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HK G3
The Heckler & Koch G3 (''Gewehr'' 3) is a 7.62×51mm NATO, selective fire, select-fire battle rifle developed in the 1950s by the German small arms, armament manufacturer Heckler & Koch (H&K) in collaboration with the Spanish state-owned design and development agency CETME (''Centro de Estudios Técnicos de Materiales Especiales''). The modular designed G3 has over the years been exported to over 70 countries and manufactured under licence in at least 15 countries, bringing the total number built to around 7,800,000. The G3 was the service rifle of the Bundeswehr, armed forces of Germany until it was replaced by the Heckler & Koch G36, G36 in the 1990s. History The origin of the G3 can be traced back to the final years of World War II when Mauser engineers at the Light Weapon Development Group (''Abteilung 37'') at Oberndorf am Neckar designed the ''Maschinenkarabiner Gerät 06'' (MKb ''Gerät'' 06, "machine carbine device 06") prototype assault rifle chambered for the inter ...
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