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Roller Locked
In firearms operating systems, the term roller locked refers to locking the bolt with rollers. Notable examples of firearms using this method are the Polish wz.37 semi-automatic rifle designed by Edward Stecke, MG 42 general-purpose machine gun, which copied the solution of engineer Stecke and the CZ 52 semi-automatic pistol. It was also applied in the experimental ''Gerät 03'' semi-automatic rifle and '' Gerät 06'' and 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 MG 3, Italian MG 42/59, and Austrian MG 74. It also spawned the Yugoslav unlicensed nearly identical Zastava M53. History The 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Rolling-element Bearing
In mechanical engineering, a rolling-element bearing, also known as a rolling bearing,ISO 15 is a bearing (mechanical), bearing which carries a load by placing rolling elements (such as balls, cylinders, or cones) between two concentric, Groove (engineering), grooved rings called Race (bearing), races. The relative motion of the races causes the rolling elements to rolling, roll with very little rolling resistance and with little sliding (motion), sliding. One of the earliest and best-known rolling-element bearings is a set 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 onto 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 "bearing (mechanical), bearings" for more on the historical development of bearings. A rolling el ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Recoil Operation
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. History The earliest mention of recoil used to assist the loading of firearms is sometimes claimed to be in 1663 when an Englishman called Palmer proposed to employ either it or gases tapped along a barrel to do so. However no one has been able to verify this claim in recent times, although there is another automatic gun that dates from the same year, but its type and method of operation are unknown. Recoil-operation, if it was invented in 1663, would then lie dormant until the 19th century, when a number of inventors started to patent designs featuring recoil operation; this was due to the fact that the integrated disposable cartridge (both bullet and propellant in one easily interchangeable unit) made these designs vi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
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 conjunction 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 pull ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Crossfire MK1
A crossfire (also known as interlocking fire) is a military term for the siting of weapons (often automatic weapons such as assault rifles or sub-machine guns) so that their arcs of fire overlap. This tactic came to prominence in World War I. Siting weapons this way is an example of the application of the defensive principle of ''mutual support''. The advantage of siting weapons that mutually support one another is that it is difficult for an attacker to find a covered approach to any one defensive position. Use of armour, air support, indirect fire support, and stealth are tactics that may be used to assault a defensive position. However, when combined with land mines, snipers, barbed wire, and air cover, crossfire became a difficult tactic to counter in the early 20th century. Early modern warfare The concept of overlapping arcs of fire drove major developments in the use of cannon in early modern Europe. The star fort forced attackers approaching the walls into the ove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Flapper Locking
Flapper locking is a type of locking mechanism used in 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 25 *Mauser 1906/08 pistol and 1905/06 rifle *Ulfbehrt (Alexander Arms) See also * Roller locked (similar) *Rotating bolt *Bolt action ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
HK G3
The Heckler & Koch G3 () is a select-fire battle rifle chambered in 7.62×51mm NATO developed in the 1950s by the German firearms manufacturer Heckler & Koch, in collaboration with the Spanish state-owned firearms manufacturer CETME. The G3 was the service rifle of the German ''Bundeswehr'' until it was replaced by the Heckler & Koch G36 in the 1990s, and was adopted into service with numerous other countries. The G3 has been exported to over 70 countries and manufactured under license in at least 15 countries. Over 7.8 million G3s have been produced. Its modular design was used for several other HK firearm models, including the HK21, MP5, HK33, PSG1, and G41. 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Blowback (arms)
Blowback is a system of operation for self-loading firearms that obtains energy from the motion of the cartridge case as it is pushed to the rear by expanding gas created by the ignition of the propellant charge. Several blowback systems exist within this broad principle of operation, each distinguished by the methods used to control bolt movement. In most actions that use blowback operation, the breech is not locked mechanically at the time of firing: the inertia of the bolt and recoil , relative to the weight of the bullet, delay opening of the breech until the bullet has left the barrel. A few locked breech designs use a form of blowback (example: primer actuation) to perform the unlocking function. The blowback principle may be considered a simplified form of gas operation, since the cartridge case behaves like a piston driven by the powder gases. Other operating principles for self-loading firearms include delayed blowback, blow forward, gas operation, and recoil ope ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Gas-operated Reloading
Gas-operation is a system of operation used to provide energy to operate locked breech, autoloading firearms. In gas-operation, a portion of high-pressure gas from the cartridge being fired is used to power a mechanism to dispose of the spent case and insert a new cartridge into the chamber. Energy from the gas is harnessed through either a port in the barrel or a trap at the muzzle. This high-pressure gas impinges on a surface such as a piston head to provide motion for unlocking of the action, extraction of the spent case, ejection, cocking of the hammer or striker, chambering of a fresh cartridge, and locking of the action. History The first mention of using a gas piston in a single-shot breech-loading rifle comes from 1856, by the German Edward Lindner who patented his invention in the United States and Britain. In 1866, Englishman William Curtis filed the first patent on a gas-operated repeating rifle but subsequently failed to develop that idea further. Between 1883 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
40 S&W
The .40 S&W (10.2×22mm) is a Rim (firearms), rimless pistol Cartridge (firearms), cartridge developed jointly by American firearms manufacturers Smith & Wesson and U.S. Repeating Arms Company, Winchester in 1990. The .40 S&W was developed as a law enforcement cartridge designed to duplicate performance of the Federal Bureau of Investigation's (FBI) reduced-velocity 10mm Auto cartridge which could be retrofitted into medium-frame (9 mm size) semi-automatic handguns. It uses bullets ranging in weight from .''Hornady Handbook of Cartridge Reloading'', Fourth Edition (1991), pp. 593–595 History In the aftermath of the 1986 FBI Miami shootout, in which two FBI special agents were killed and five wounded, the FBI started the process of testing 9×19mm Parabellum and .45 ACP ammunition in preparation to replace its standard-issue revolver with a semi-automatic pistol. The semi-automatic pistol offered two advantages over the revolver: increased ammunition capacity and increased e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
9×19mm Parabellum
The 9×19mm Parabellum (also known as 9mm Luger, 9mm NATO or simply 9mm) is a Rim (firearms)#Rimless, rimless, Centerfire ammunition, centerfire, tapered cartridge (firearms), firearms cartridge. Originally designed by Austrian firearm designer Georg Luger in 1901, it is widely considered the most popular handgun and submachine gun cartridge due to its low cost, adequate stopping power and extensive availability. Since the cartridge was designed for the Luger pistol, Luger semi-automatic pistol, it has been given the designation of ''9mm Luger'' by the Sporting Arms and Ammunition Manufacturers' Institute (SAAMI) and the (CIP). A 2007 US survey concluded that "about 60 percent of the firearms in use by police are 9mm [Parabellum]" and credited 9×19mm Parabellum pistol sales with making semiautomatic pistols more popular than revolvers.Adler, Jerry, et al. (30 April 2007)"Story of a Gun"(). ''Newsweek'' 149.18: 36–39. MasterFILE Premier. EBSCO. Dallas Public Library, Dallas, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Semi-automatic Rifle
A semi-automatic rifle is a type of rifle that fires a single round each time the Trigger (firearms), trigger is pulled while automatically loading the next Cartridge (firearms), cartridge. These rifles were developed Pre-World War II, and were used throughout World War II. Rifles are firearms designed to be fired while held with both hands and braced against the shooter's shoulder for stability. Externally similar shotguns can fire multiple Shot (pellet), pellets simultaneously through a smoothbore, while rifle Gun barrel, barrels are Rifling, rifled to spin-stabilize individual bullets. The actions of semi-automatic rifles use a portion of the fired cartridge's energy to eject the spent casing and load a new round into the Chamber (firearms), chamber, readying the rifle to be fired again. This design differs from manually operated rifles such as Bolt action, bolt-action and Lever action, lever-action rifles, which need to chamber a cartridge manually before firing again, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
