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Sabot (firearms)
A sabot (, ) is a supportive device used in firearm/artillery ammunitions to fit/patch around a projectile, such as a bullet/shotgun slug, slug or a flechette-like projectile (such as a kinetic energy penetrator), and keep it aligned in the center of the barrel (firearms), barrel when fired. It allows a narrower projectile with high sectional density to be fired through a gun barrel, barrel of much larger caliber, bore diameter with maximal acceleration, accelerative transfer of kinetic energy. After leaving the muzzle (firearms), muzzle, the sabot typically separates from the projectile in flight, diverting only a very small portion of the overall kinetic energy. The sabot component in projectile design is the relatively thin, tough and deformable seal known as a driving band or obturation ring needed to trap propellant gases behind a projectile, and also keep the projectile centered in the barrel, when the outer shell of the projectile is only slightly smaller in diameter than t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Armour-piercing Discarding Sabot
Armour-piercing discarding sabot (APDS) is a type of spin-stabilized kinetic energy projectile for anti-armour warfare. Each projectile consists of a sub-calibre round fitted with a sabot. The combination of a lighter sub-calibre projectile with a full-calibre propellant charge allows for an increase in muzzle velocity compared to full-calibre rounds, giving the round increased armour-penetration performance. To further enhance their armour-penetration capabilities, APDS rounds typically feature a hardened core made from tungsten or another hard, dense material. For a given calibre, APDS ammunition can effectively double the armour penetration of a gun when compared to full-calibre rounds such as AP, Armour-piercing Capped (APC), and Armour piercing Capped Ballistic Cap (APCBC) projectiles. APDS-rounds were commonly used in large calibre tank guns up until the early 1980s, but have since been superseded by armour-piercing fin-stabilized discarding sabot (APFSDS) projectiles, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kinetic Energy
In physics, the kinetic energy of an object is the energy that it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes. The same amount of work is done by the body when decelerating from its current speed to a state of rest. Formally, a kinetic energy is any term in a system's Lagrangian which includes a derivative with respect to time. In classical mechanics, the kinetic energy of a non-rotating object of mass ''m'' traveling at a speed ''v'' is \fracmv^2. In relativistic mechanics, this is a good approximation only when ''v'' is much less than the speed of light. The standard unit of kinetic energy is the joule, while the English unit of kinetic energy is the foot-pound. History and etymology The adjective ''kinetic'' has its roots in the Greek word κίνησις ''kinesis'', m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
M829
The M829 is an American armor-piercing, fin-stabilized, discarding sabot (APFSDS) tank round. Modeling was designed at the Ballistic Research Laboratory (BRL) at Aberdeen Proving Ground (APG), which was incorporated into the Army Research Laboratory (ARL) in 1992. The round is specifically modeled for the 120 mm M256 main gun on the Abrams M1A1 and M1A2 main battle tanks. The penetrator is carried by a sabot during its acceleration in the gun barrel. Variants M829 The M829 has a ballistic nose and five tail fins made of aluminum. It is carried in the gun tube by a three-piece aluminum sabot, which separates into three "petals" soon after the round leaves the gun tube. The propulsion system uses an obturating case base with a semi-combustible cartridge wall. It has a total weight of and utilizes a DU penetrator with a rod diameter, which will reach a muzzle velocity of using of JA-2 propellant. Maximum effective range is . According to Jane's, the M829 is capable of pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Finite Element Method In Structural Mechanics
The finite element method (FEM) is a powerful technique originally developed for numerical solution of complex problems in structural mechanics, and it remains the method of choice for complex systems. In the FEM, the structural system is modeled by a set of appropriate finite elements interconnected at discrete points called nodes. Elements may have physical properties such as thickness, coefficient of thermal expansion, density, Young's modulus, shear modulus and Poisson's ratio. History The origin of finite method can be traced to the matrix analysis of structures where the concept of a displacement or stiffness matrix approach was introduced. Finite element concepts were developed based on engineering methods in 1950s. The finite element method obtained its real impetus in the 1960s and 1970s by John Argyris, and co-workers; at the University of Stuttgart, by Ray W. Clough; at the University of California, Berkeley, by Olgierd Zienkiewicz, and co-workers Ernest Hinton, Br ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Armor-piercing Fin-stabilized Discarding Sabot
Armour-piercing fin-stabilized discarding sabot (APFSDS), long dart penetrator, or simply dart ammunition, is a type of kinetic energy penetrator ammunition used to attack modern vehicle armour. As an armament for main battle tanks, it succeeds Armour-Piercing Discarding Sabot (APDS) ammunition, which is still used in small or medium caliber weapon systems. Improvements in powerful automotive propulsion and suspension systems following World War II allowed modern main battle tanks to incorporate progressively thicker and heavier armour protection systems, while maintaining considerable maneuverability and speed on the battlefield. As a result, achieving deep armour penetration with gun-fired ammunition required even longer anti-armour projectiles fired at even higher muzzle velocity than could be achieved with stubbier APDS projectiles. History Armour-piercing discarding sabot (APDS) was initially the main design of the kinetic energy (KE) penetrator. The logical progression ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Armor-piercing Discarding Sabot
Armour-piercing discarding sabot (APDS) is a type of spin-stabilized kinetic energy projectile for anti-armour warfare. Each projectile consists of a sub-calibre round fitted with a sabot. The combination of a lighter sub-calibre projectile with a full-calibre propellant charge allows for an increase in muzzle velocity compared to full-calibre rounds, giving the round increased armour-penetration performance. To further enhance their armour-penetration capabilities, APDS rounds typically feature a hardened core made from tungsten or another hard, dense material. For a given calibre, APDS ammunition can effectively double the armour penetration of a gun when compared to full-calibre rounds such as AP, Armour-piercing Capped (APC), and Armour piercing Capped Ballistic Cap (APCBC) projectiles. APDS-rounds were commonly used in large calibre tank guns up until the early 1980s, but have since been superseded by armour-piercing fin-stabilized discarding sabot (APFSDS) projectiles, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interior 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 chamber ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
External Links
An internal link is a type of hyperlink on a web page to another page or resource, such as an image or document, on the same website or domain. Hyperlinks are considered either "external" or "internal" depending on their target or destination. Generally, a link to a page outside the same domain or website is considered external, whereas one that points at another section of the same web page or to another page of the same website or domain is considered internal. These definitions become clouded, however, when the same organization operates multiple domains functioning as a single web experience, e.g. when a secure commerce website is used for purchasing things displayed on a non-secure website. In these cases, links that are "external" by the above definition can conceivably be classified as "internal" for some purposes. Ultimately, an internal link points to a web page or resource in the same root directory. Similarly, seemingly "internal" links are in fact "external" for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Windage
Windage is a term used in aerodynamics, firearms ballistics, and automobiles. Usage Aerodynamics Windage is a force created on an object by friction when there is relative movement between air and the object. Windage loss is the reduction in efficiency due to windage forces. For example, electric motors are affected by friction between the rotor and air. Large alternators have significant losses due to windage. To reduce losses, hydrogen gas may be used, since it is less dense. There are two causes of windage: # The object is moving and being slowed by resistance from the air. # A wind is blowing, producing a force on the object. The term can refer to: * The effect of the force, for example the deflection of a missile or an aircraft by a cross wind. * The area and shape of the object that make it susceptible to friction, for example those parts of a boat that are exposed to the wind. Aerodynamic streamlining can be used to reduce windage. There is a hydrodynamic effect si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propellant
A propellant (or propellent) is a mass that is expelled or expanded in such a way as to create a thrust or other motive force in accordance with Newton's third law of motion, and "propel" a vehicle, projectile, or fluid payload. In vehicles, the engine that expels the propellant is called a reaction engine. Although technically a propellant is the reaction mass used to create thrust, the term "propellant" is often used to describe a substance which is contains both the reaction mass and the fuel that holds the energy used to accelerate the reaction mass. For example, the term "propellant" is often used in chemical rocket design to describe a combined fuel/propellant, although the propellants should not be confused with the fuel that is used by an engine to produce the energy that expels the propellant. Even though the byproducts of substances used as fuel are also often used as a reaction mass to create the thrust, such as with a chemical rocket engine, propellant and fuel are two ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
