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Bullpup Rifles
A bullpup firearm is one with its firing grip located in front of the Chamber (firearms), breech of the weapon, instead of behind it. This creates a weapon with a shorter overall length for a given barrel length, and one that is often lighter, more compact, concealable, and more maneuverable than a conventionally configured firearm. Where it is desirable for troops to be issued a more compact weapon, the use of a bullpup configuration allows for barrel length to be retained, thus preserving muzzle velocity, range, and ballistic effectiveness. The bullpup concept was first tested militarily in 1901 with the British Thorneycroft carbine, but it was not until the Cold War that more successful designs and improvements led to wider adoption. In 1977, the Austrian Federal Army, Austrian Army became the first military force in the world to adopt a bullpup rifle, the Steyr AUG, as a service rifle, principal combat weapon. Since then the militaries in many countries have followed suit w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dragunov SVU
The OTs-03 SVU (, , Sniper Rifle Shortened) is a bullpup designated marksman rifle. The SVU was developed to meet the needs of the security forces of the Russian Ministry of Internal Affairs, such as OMON. The SVU was first seen in use in the First Chechen War. Originally, the plan was to just slightly modernize the aging Dragunov sniper rifle, SVD, but the designers eventually realised that the configuration of the weapon would have to be completely altered, leading to the creation of the SVU. A special muzzle brake was added that could absorb up to 40% of the recoil energy and an elastic butt stock with lamellar spring was non-rigidly attached to the receiver. The acoustics of the rifle were also improved by adding a sound suppressor. The other main improvements made to the SVU over the SVD include replacement of the butt stock, pistol grip, trigger and the mounting for the sight; and shortening the barrel by achieved perfect balance for the weapon. Around 1991, the Russians d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bulldog
The Bulldog is a British breed of dog of mastiff type. It may also be known as the English Bulldog or British Bulldog. It is a stocky, muscular dog of medium size, with a large head, thick folds of skin around the face and shoulders and a relatively flat face with a protruding lower jaw. Selective breeding for appearance has led to increased susceptibility to health problems including brachycephaly, hip dysplasia, heat sensitivity and skin infections. The dogs may not be bred in Norway or the Netherlands, because of concerns about their quality of life. The modern Bulldog was bred as a companion dog from the Old English Bulldog, a now-extinct breed used for bull-baiting until that was outlawed under the Cruelty to Animals Act of 1835. The Bulldog Club (in England) was formed in 1878, and the Bulldog Club of America was formed in 1890. While often used as a symbol of ferocity and courage, the modern Bulldog is generally a friendly, amiable dog. It is commonly kept as a pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Recoil
Recoil (often called knockback, kickback or simply kick) is the rearward thrust generated when a gun is being discharged. In technical terms, the recoil is a result of conservation of momentum, for according to Newton's third law the force required to accelerate something will evoke an equal but opposite reactional force, which means the forward momentum gained by the projectile and exhaust gases (ejectae) will be mathematically balanced out by an equal and opposite momentum exerted back upon the gun. Basics Any launching system (weapon or not) generates recoil. However recoil only constitutes a problem in the field of artillery and firearms due to the magnitude of the forces at play. Gun chamber pressures and projectile acceleration forces are tremendous, on the order of tens to hundreds mega pascalAs a perspective, the atmospheric pressure is roughly 0.1 megapascal. and tens of thousands of times the acceleration of gravity ( g's), both necessary to launch the projectile a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kinematic
In physics, kinematics studies the geometrical aspects of motion of physical objects independent of forces that set them in motion. Constrained motion such as linked machine parts are also described as kinematics. Kinematics is concerned with systems of specification of objects' positions and velocities and mathematical transformations between such systems. These systems may be rectangular like cartesian, Curvilinear coordinates like polar coordinates or other systems. The object trajectories may be specified with respect to other objects which may themselve be in motion relative to a standard reference. Rotating systems may also be used. Numerous practical problems in kinematics involve constraints, such as mechanical linkages, ropes, or rolling disks. Overview Kinematics is a subfield of physics and mathematics, developed in classical mechanics, that describes the motion of points, bodies (objects), and systems of bodies (groups of objects) without considering the forces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torque
In physics and mechanics, torque is the rotational analogue of linear force. It is also referred to as the moment of force (also abbreviated to moment). The symbol for torque is typically \boldsymbol\tau, the lowercase Greek letter ''tau''. When being referred to as moment of force, it is commonly denoted by . Just as a linear force is a push or a pull applied to a body, a torque can be thought of as a twist applied to an object with respect to a chosen point; for example, driving a screw uses torque to force it into an object, which is applied by the screwdriver rotating around its axis to the drives on the head. Historical terminology The term ''torque'' (from Latin , 'to twist') is said to have been suggested by James Thomson and appeared in print in April, 1884. Usage is attested the same year by Silvanus P. Thompson in the first edition of ''Dynamo-Electric Machinery''. Thompson describes his usage of the term as follows: Today, torque is referred to using d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Core (anatomy)
The core or trunk is the axial skeleton, axial (central) part of an organism's body (biology), body. In common parlance, the term is broadly considered to be synonymous with the torso, but academically it also includes the head and neck. Functional movements are highly dependent on this part of the body, and lack of core muscular development can result in a predisposition to injury. The major muscles of the core reside in the area of the belly and the mid- and lower back (not the shoulders), and peripherally include the hips, the shoulders and the neck. Muscles Major muscles included are the pelvic floor muscles, transversus abdominis, multifidus, internal oblique, internal and external obliques, rectus abdominis, erector spinae (sacrospinalis) especially the longissimus thoracis, and the diaphragm (anatomy), diaphragm. The lumbar muscles, quadratus Lumborum (deep portion), deep rotators, as well as cervical muscles, rectus capitus anterior and lateralis, longus coli may also b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Center Of Mass
In physics, the center of mass of a distribution of mass in space (sometimes referred to as the barycenter or balance point) is the unique point at any given time where the weight function, weighted relative position (vector), position of the distributed mass sums to zero. For a rigid body containing its center of mass, this is the point to which a force may be applied to cause a linear acceleration without an angular acceleration. Calculations in mechanics are often simplified when formulated with respect to the center of mass. It is a hypothetical point where the entire mass of an object may be assumed to be concentrated to visualise its motion. In other words, the center of mass is the particle equivalent of a given object for application of Newton's laws of motion. In the case of a single rigid body, the center of mass is fixed in relation to the body, and if the body has uniform density, it will be located at the centroid. The center of mass may be located outside the Phys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neostead
The NeoStead 2000 (NS2000) is a bullpup combat shotgun developed by Truvelo Armoury of South Africa. Production of the shotgun began in 2001 and the first models were made available in October of that same year. It is notable due to its unusual forward-and-back pump-action cycling motion. Design and production The NS2000 is a 12-gauge pump-action shotgun weighing just under , designed primarily for security and civil disturbance situations. The firearm includes a barrel despite the overall weapon length of just . The short length makes the weapon easier to handle in close-quarters situations; however it can still remain accurate at relatively long ranges. The long barrel length is achieved by using a bullpup configuration, with a rear-fed tubular magazine. Another aspect of the NS2000 is its dual six-round (6+6) magazine. The selector switch can be set to left, right, or alternating. In riot conditions, for example, less-lethal flexible baton rounds can be used with st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FN P90
The FN P90 is a personal defense weapon chambered for the 5.7×28mm cartridge, also classified as a submachine gun, designed and manufactured by FN Herstal in Belgium. Created in response to NATO requests for a replacement for 9×19mm Parabellum firearms, the P90 was designed as a compact but powerful firearm for vehicle crews, operators of crew-served weapons, support personnel, special forces, and counter-terrorist groups. Designed in conjunction with the FN Five-seven pistol and FN 5.7×28mm NATO ammunition, development of the weapon began in 1986, and production commenced in 1990, when it was known as the ''Project 9.0'' (from which the "90" in its name is derived), whereupon the 5.7×28mm ammunition was redesigned and shortened. A modified version of the P90 with a magazine adapted to use the new ammunition was introduced in 1993, and the Five-seven pistol was subsequently introduced as a companion weapon using the same 5.7×28mm ammunition. Featuring a compact bull ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heckler & Koch G11
The Heckler & Koch G11 is a non-production prototype assault rifle developed from the late 1960s to the 1980s by ''Gesellschaft für Hülsenlose Gewehrsysteme'' (GSHG) (German for "Association for Caseless Rifle Systems"), a conglomeration of companies headed by firearm manufacturer Heckler & Koch (mechanical engineering and weapon design), Dynamit Nobel (propellant composition and projectile design), and Hensoldt Wetzlar (target identification and optic systems). The rifle is noted for its use of caseless ammunition. It was primarily a project of West Germany, though it was of significance to the other NATO countries as well. In particular, versions of the G11 were included in the U.S. Advanced Combat Rifle program. In 1990, H&K finished the development of the G11, intended for the ''Bundeswehr'' and other NATO partners. Although the weapon was a technical success, it never entered full production due to the political changes of German reunification and lack of procurement co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magazine (firearms)
A magazine, often simply called a mag, is an ammunition storage and feeding device for a repeating firearm, either integral within the gun (internal/fixed magazine) or externally attached (detachable magazine). The magazine functions by holding several cartridge (firearms), cartridges within itself and sequentially pushing each one into a position where it may be readily loaded into the gun barrel, barrel chamber (firearms), chamber by the firearm's moving action (firearms), action. The detachable magazine is sometimes colloquially referred to as a "clip (ammunition), clip", although this is technically inaccurate since a clip is actually an accessory device used to help load ammunition into a magazine or cylinder. Magazines come in many shapes and sizes, from integral tubular magazines on lever-action and pump-action rifles and shotguns, that may hold more than five rounds, to detachable box magazines and drum magazines for automatic rifles and light machine guns, that may h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buttstock
A gunstock or often simply stock, the back portion of which is also known as a shoulder stock, a buttstock, or simply a butt, is a part of a long gun that provides structural support, to which the barrel, action, and firing mechanism are attached. The stock also provides a means for the shooter to firmly brace the gun and easily aim with stability by being held against the user's shoulder when shooting the gun, and helps to counter muzzle rise by transmitting recoil straight into the shooter's body. The tiller of a crossbow is functionally the equivalent of the stock on a gun. History and etymology The term stock in reference to firearms dates to 1571 is derived from the Germanic word ''Stock'', meaning tree trunk, referring to the wooden nature of the gunstock. Early hand cannons used a simple stick fitted into a socket in the breech end to provide a handle. The modern gunstock shape began to evolve with the introduction of the arquebus, a matchlock with a longer barrel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
