|
Bolt Thrust
Bolt thrust or breech pressure is a term used in internal ballistics and firearms (whether small arms or artillery) that describes the amount of rearward force exerted by the propellant gases on the bolt or breech of a firearm action or breech when a projectile is fired. The applied force has both magnitude and direction, making it a vector quantity. Bolt thrust is an important factor in weapons design. The greater the bolt thrust, the stronger the locking mechanism has to be to withstand it. Assuming equal engineering solutions and material adding strength to a locking mechanism causes an increase in weight and size of locking mechanism components. Bolt thrust is not a measure to determine the amount of recoil or free recoil. Calculating bolt thrust With a basic calculation the bolt thrust produced by a particular firearms cartridge can be calculated fairly accurately. Formula :\vec_ = P_ \cdot A_. where: *''Fbolt'' = the amount of bolt thrust *''Pmax'' = the maximum (pea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internal Ballistics
Internal ballistics (also interior ballistics), a subfield of ballistics, is the study of the propulsion of a projectile. In guns, internal ballistics covers the time from the propellant's ignition until the projectile exits the gun barrel. The study of internal ballistics is important to designers and users of firearms of all types, from small-bore rifles and pistols, to high-tech artillery. For rocket-propelled projectiles, internal ballistics covers the period during which a rocket motor is providing thrust. Parts and equations Hatcher breaks the duration of interior ballistics into three parts: *Lock time, the time from sear release until the primer is struck *Ignition time, the time from when the primer is struck until the projectile starts to move *Barrel time, the time from when the projectile starts to move until it exits the barrel. There are many processes that are significant. The source of energy is the burning propellant. It generates hot gases that raise the chamb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NATO EPVAT Testing
NATO EPVAT testing is one of the three recognized classes of procedures used in the world to control the safety and quality of firearms ammunition. Beside this, there are also the ''Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives'' (C.I.P.) class of procedures and the Sporting Arms and Ammunition Manufacturers' Institute (SAAMI) class of procedures. EPVAT Testing is described in unclassified documents by NATO, more precisely by the AC/225 Army Armaments Group (NAAG). EPVAT is an abbreviation for "Electronic Pressure Velocity and Action Time". Action Time here means the (short amount of) time required between the ignition of the primer and the projectile leaving the barrel. This is a comprehensive procedure for testing ammunition using state-of-the-art instruments and computers. The procedure itself is described in NATO document AC/225 (Com. III/SC.1)D/200. Unlike the C.I.P. procedures aiming only at the user's safety, the NATO procedures for ammu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
10 Mm Auto
The 10mm Auto (10×25mm, official C.I.P. nomenclature: 10 mm Auto, official SAAMI nomenclature: 10mm Automatic) is a semi-automatic pistol cartridge introduced in 1983. Its design was adopted and later produced by ammunition manufacturer FFV Norma AB of Åmotfors, Sweden. Although it was selected for service by the Federal Bureau of Investigation (FBI) in 1989, in the aftermath of the 1986 FBI Miami shootout, the cartridge was later decommissioned (except by the Hostage Rescue Team and Special Weapons and Tactics Teams) after their Firearms Training Unit eventually concluded that its recoil was excessive in terms of training for average agents and police officers' competency of use and qualification, and that the pistols chambered for the cartridge were too large for some small-handed individuals. These issues led to the creation of and following replacement by a shorter version of the 10mm that exists today as the .40 S&W, and while the 10mm never attained the mainstream ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
40 S&W
The .40 S&W is a rimless pistol cartridge developed jointly by American firearms manufacturers Smith & Wesson and 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 (9mm size) semi-automatic handguns. It uses diameter 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 ease of reloading during a gunfight. The FBI was satisfied with the perf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
380 ACP '', 2001
{{Numberdis ...
38 may refer to: *38 (number), the natural number following 37 and preceding 39 *one of the years 38 BC, AD 38, 1938, 2038 *.38, a caliber of firearms and cartridges **.38 Special, a revolver cartridge *'' Thirty-Eight: The Hurricane That Transformed New England'', a 2016 book by Stephen Long *"Thirty Eight", a song by Karma to Burn from the album ''Almost Heathen ''Almost Heathen'' is the third studio album by the stoner rock band Karma to Burn Karma to Burn, commonly abbreviated as K2B, is a desert rock/ stoner rock band from Morgantown, West Virginia. The band are noted for their uncompromising, mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
357 SIG
The .357 SIG (designated as the 357 Sig by the SAAMI and 357 SIG by the C.I.P. or 9×22mm in unofficial metric notation) is a bottlenecked rimless centerfire handgun cartridge developed by the Swiss-German firearms manufacturer SIG Sauer, in cooperation with ammunition manufacturer Federal Premium. The cartridge is used by a number of law enforcement agencies.''The Gun Digest Book of Sig-Sauer: a complete look at Sig-Sauer pistols.'' Massad Ayoob. 2004. pp. 51–53. History The .357 SIG is based on a necked-down 10mm Auto case. Other than specialized competition cartridges like the 9×25mm Dillon (1988), which necked a 10mm Auto case down to a 9 mm bullet, the .357 SIG (1994) was the first modern bottleneck commercial handgun cartridge since the early 1960s, when Winchester introduced a .257 caliber round based on the .357 Magnum, the now obsolete .256 Winchester Magnum (1960). Then Remington introduced the unsuccessful .22 Remington Jet (1961), which necked a .357 Ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
22 Long Rifle
The .22 Long Rifle or simply .22 LR or 22 (metric designation: 5.6×15mmR) is a long-established variety of .22 caliber rimfire ammunition originating from the United States. It is used in a wide range of rifles, pistols, revolvers, smoothbore shotguns, and submachine guns. In terms of units sold it is by far the most common ammunition in the world today. Common uses include hunting and shooting sports. Ammunition produced in .22 Long Rifle is effective at short ranges, has little recoil, and is cheap to purchase, making it ideal for training. History American firearms manufacturer J. Stevens Arms & Tool Company introduced the .22 Long Rifle cartridge in 1887. The round owes its origin to the .22 BB Cap of 1845 and the .22 Short of 1857. It combined the case of the .22 Long of 1871 with a bullet, giving it a longer overall length, a higher muzzle velocity and superior performance as a hunting and target round, rendering the .22 Extra Long cartridges obsolete. The .22 LR ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kilogram-force
The kilogram-force (kgf or kgF), or kilopond (kp, from la, pondus, lit=weight), is a non-standard gravitational metric unit of force. It does not comply with the International System of Units (SI) and is deprecated for most uses. The kilogram-force is equal to the magnitude of the force exerted on one kilogram of mass in a gravitational field ( standard gravity, a conventional value approximating the average magnitude of gravity on Earth). That is, it is the weight of a kilogram under standard gravity. Therefore, one kilogram-force is by definition equal to . NISTbr>''Guide for the Use of the International System of Units (SI)''Special Publication 811, (1995) page 51 Similarly, a gram-force is , and a milligram-force is . Kilogram-force is a non-standard unit and is classified in the International System of Units (SI) as a unit that is not accepted for use with SI. History The gram-force and kilogram-force were never well-defined units until the CGPM adopted a ''standard a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bar (unit)
The bar is a metric unit of pressure, but not part of the International System of Units (SI). It is defined as exactly equal to 100,000 Pa (100 kPa), or slightly less than the current average atmospheric pressure on Earth at sea level (approximately 1.013 bar). By the barometric formula, 1 bar is roughly the atmospheric pressure on Earth at an altitude of 111 metres at 15 °C. The bar and the millibar were introduced by the Norwegian meteorologist Vilhelm Bjerknes, who was a founder of the modern practice of weather forecasting. The International System of Units, despite previously mentioning the bar, now omits any mention of it.. The bar has been legally recognised in countries of the European Union since 2004.British Standard BS 350:2004 ''Conversion Factors for Units''. The US National Institute of Standards and Technology (NIST) deprecates its use except for "limited use in meteorology" and lists it as one of several units that "must not be introduce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cooking Off
Cooking off (or thermally induced firing) is unfired weapon ammunition exploding prematurely due to heat in the surrounding environment. The term is used both for detonation of ammunition not loaded into a weapon, and unintended firing of a loaded weapon due to heating. A fast cook-off is a cook-off caused by fire. A slow cook-off is caused by a sustained thermal event less intense than fire. A cooked-off round may cause a sympathetic detonation of adjacent rounds. Insensitive munitions are designed to be less vulnerable to accidental firing induced by external heat. Artillery Inherent design flaws in early 17th century Swedish leather cannons led to the gun tube overheating which prematurely ignited the gunpowder, injuring the loader. Muzzle-loading cannon on merchant and naval vessels of the Age of Sail would fire if the vessels caught fire while the guns were loaded. Examples include the merchantman and . After the cooking off of artillery shells in the G5 howitze ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chamber (firearms)
In firearms, the chamber is the cavity at the back end of a breechloader's barrel or cylinder, where the cartridge is inserted before being fired. The rear opening of the chamber is the breech, and is sealed by the breechblock or the bolt. Function Rifles and pistols generally have a single chamber integral to their barrels, but revolvers have multiple chambers in their cylinder, and no chamber in their barrel. Thus, rifles and pistols can usually still be fired with the magazine removed as long as a cartridge is inserted into the chamber, while a revolver cannot be fired at all with its cylinder swung out. The act of ''chambering'' a cartridge means the insertion of a round into the chamber, either manually or through the action of the weapon, e.g., pump-action, lever-action, bolt action, or Autoloading operation generally in anticipation of firing the weapon, without need to "load" the weapon upon decision to use it (reducing the number of ''actions'' needed to d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
