14.5×114mm Anti-materiel Rifles
The 14.5×114mm (.57 calibre) is a heavy machine gun and anti-materiel rifle cartridge used by the Soviet Union, the former Warsaw Pact, modern Russia, and other countries. It was originally developed for the PTRS and PTRD anti-tank rifles, and was later used as the basis for the KPV heavy machine gun that formed the basis of the ZPU series anti-aircraft guns that is also the main armament of the BTR series of armoured personnel carriers from the BTR-60 to the BTR-80 and for heavy anti-materiel sniper rifles. Cartridge dimensions The 14.5×114mm has 42.53 ml (655 grains H2O) cartridge case capacity. The exterior shape of the case was designed to promote reliable case feeding and extraction in bolt-action rifles and machine guns alike, under extreme conditions. 14.5×114mm maximum cartridge dimensions. All dimensions in millimetres (mm). Americans define the shoulder angle at alpha/2 = 22.5 degrees. The common rifling twist rate for this cartridge is 455 mm (1 ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Soviet Union
The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen national republics; in practice, both its government and its economy were highly centralized until its final years. It was a one-party state governed by the Communist Party of the Soviet Union, with the city of Moscow serving as its capital as well as that of its largest and most populous republic: the Russian SFSR. Other major cities included Leningrad (Russian SFSR), Kiev (Ukrainian SSR), Minsk ( Byelorussian SSR), Tashkent (Uzbek SSR), Alma-Ata (Kazakh SSR), and Novosibirsk (Russian SFSR). It was the largest country in the world, covering over and spanning eleven time zones. The country's roots lay in the October Revolution of 1917, when the Bolsheviks, under the leadership of Vladimir Lenin, overthrew the Russian Provisional Government ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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BTR-80
The BTR-80 (russian: бронетранспортёр, bronyetransportyor, literally "armoured transporter") is an 8×8 wheeled amphibious armoured personnel carrier (APC) designed in the USSR. It was adopted in 1985 and replaced the previous vehicles, the BTR-60 and BTR-70, in the Soviet Army. It was first deployed during the Soviet–Afghan War. The BTR-80 was developed into the larger BTR-90. Description The Soviets based the BTR-80 on the BTR-70 APC, which itself was based on the BTR-60. It has a single 260-hp V-8 turbocharged water-cooled diesel engine, an improvement over the twin gasoline engines installed in the BTR-60 and BTR-70 vehicles. The reconfigured rear portion of the hull accommodates the new, single engine. The Soviets removed the roof chamfers of the modified BTR-70, raised the rear, and squared off the rearward-sloping engine compartment. Standard equipment includes TNPO vision blocks, TNP-B and TKN-3 optical devices for the driver and commander, an OU ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Tungsten Carbide
Tungsten carbide (chemical formula: WC) is a chemical compound (specifically, a carbide) containing equal parts of tungsten and carbon atoms. In its most basic form, tungsten carbide is a fine gray powder, but it can be pressed and formed into shapes through sintering for use in industrial machinery, cutting tools, chisels, abrasives, armor-piercing shells and jewelry. Tungsten carbide is approximately twice as stiff as steel, with a Young's modulus of approximately 530–700 GPa, and is double the density of steel—nearly midway between that of lead and gold. It is comparable with corundum (α-) in hardness and can be polished and finished only with abrasives of superior hardness such as cubic boron nitride and diamond powder, wheels and compounds. Naming Historically referred to as Wolfram, ''Wolf Rahm'', wolframite ore was then later carburized and cemented with a binder creating a composite now called "tungsten carbide". Tungsten is Swedish for "heavy stone". Col ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Incendiary Device
Incendiary weapons, incendiary devices, incendiary munitions, or incendiary bombs are weapons designed to start fires or destroy sensitive equipment using fire (and sometimes used as anti-personnel weaponry), that use materials such as napalm, thermite, magnesium powder, chlorine trifluoride, or white phosphorus. Though colloquially often known as bombs, they are not explosives but in fact are designed to slow the process of chemical reactions and use ignition rather than detonation to start or maintain the reaction. Napalm for example, is petroleum especially thickened with certain chemicals into a 'gel' to slow, but not stop, combustion, releasing energy over a longer time than an explosive device. In the case of napalm, the gel adheres to surfaces and resists suppression. Pre-modern history A range of early thermal weapons were utilized by ancient, medieval/post-classical and early modern armies, including hot pitch, oil, resin, animal fat and other similar compounds. Subs ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Armor Piercing
Armour-piercing ammunition (AP) is a type of projectile designed to penetrate either body armour or vehicle armour. From the 1860s to 1950s, a major application of armour-piercing projectiles was to defeat the thick armour carried on many warships and cause damage to their lightly-armoured interiors. From the 1920s onwards, armour-piercing weapons were required for anti-tank warfare. AP rounds smaller than 20 mm are intended for lightly-armoured targets such as body armour, bulletproof glass, and lightly-armoured vehicles. As tank armour improved during World War II, anti-vehicle rounds began to use a smaller but dense penetrating body within a larger shell, firing at very high muzzle velocity. Modern penetrators are long rods of dense material like tungsten or depleted uranium (DU) that further improve the terminal ballistics. History The late 1850s saw the development of the ironclad warship, which carried wrought iron armour of considerable thickness. This armour w ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Proof (firearms)
A proof test is a form of stress test to demonstrate the fitness of a load-bearing structure. An individual proof test may apply only to the unit tested, or to its design in general for mass-produced items. Such a structure is often subjected to loads above that expected in actual use, demonstrating safety and design margin. Proof testing is nominally a nondestructive test, particularly if both design margins and test levels are well-chosen. However, unit failures are by definition considered to have been destroyed for their originally-intended use and load levels. Proof tests may be performed before a new design or unit is allowed to enter service, or perform additional uses, or to verify that an existing unit is still functional as intended.Test intervals for in-service ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Twist Rate
In firearms, rifling is machining helical grooves into the internal (bore) surface of a gun's barrel for the purpose of exerting torque and thus imparting a spin to a projectile around its longitudinal axis during shooting to stabilize the projectile longitudinally by conservation of angular momentum, improving its aerodynamic stability and accuracy over smoothbore designs. Rifling is characterized by its twist rate, which indicates the distance the rifling takes to complete one full revolution, such as "1 turn in 10 inches" (1:10 inches), "1 turn in 254 mm" ("1:254 mm" or "1:25.4 cm)", or the like. Normally, an experienced shooter can infer the units of measurement from the numbers alone. A shorter distance indicates a faster twist, meaning that for a given velocity the projectile will rotate at a higher spin rate. The combination of length, weight, and shape of a projectile determines the twist rate needed to gyroscopically stabilize it – barrel ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Rifling
In firearms, rifling is machining helical grooves into the internal (bore) surface of a gun's barrel for the purpose of exerting torque and thus imparting a spin to a projectile around its longitudinal axis during shooting to stabilize the projectile longitudinally by conservation of angular momentum, improving its aerodynamic stability and accuracy over smoothbore designs. Rifling is characterized by its twist rate, which indicates the distance the rifling takes to complete one full revolution, such as "1 turn in 10 inches" (1:10 inches), "1 turn in 254 mm" ("1:254 mm" or "1:25.4 cm)", or the like. Normally, an experienced shooter can infer the units of measurement from the numbers alone. A shorter distance indicates a faster twist, meaning that for a given velocity the projectile will rotate at a higher spin rate. The combination of length, weight, and shape of a projectile determines the twist rate needed to gyroscopically stabilize it – barrel ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Machine Guns
A machine gun is a fully automatic, rifled autoloading firearm designed for sustained direct fire with rifle cartridges. Other automatic firearms such as automatic shotguns and automatic rifles (including assault rifles and battle rifles) are typically designed more for firing short bursts rather than continuous firepower, and are not considered true machine guns. As a class of military kinetic projectile weapon, machine guns are designed to be mainly used as infantry support weapons and generally used when attached to a bipod or tripod, a fixed mount or a heavy weapons platform for stability against recoils. Many machine guns also use belt feeding and open bolt operation, features not normally found on other infantry firearms. Machine guns can be further categorized as light machine guns, medium machine guns, heavy machine guns, general purpose machine guns and squad automatic weapons. Similar automatic firearms of caliber or more are classified as autocannons, rat ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Bolt-action
Bolt-action is a type of manual firearm action that is operated by ''directly'' manipulating the bolt via a bolt handle, which is most commonly placed on the right-hand side of the weapon (as most users are right-handed). Most bolt-action firearms use a rotating bolt design, where the handle must first be rotated upward to unlock the bolt from the receiver, then pulled back to open the breech and allowing any spent cartridge case to be extracted and ejected. This also cocks the striker within the bolt (either on opening or closing of the bolt depending on the gun design) and engages it against the sear. When the bolt is returned to the forward position, a new cartridge (if available) is pushed out of the magazine and into the barrel chamber, and finally the breech is closed tight by rotating the handle down so the bolt head relocks on the receiver. Bolt-action firearms are generally repeating firearms, but some single-shot breechloaders also use bolt-action design as ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |