|
Free-floating Barrel
A free-floating barrel is a firearm design used in precision rifles, particularly match grade benchrest rifles, to accurize the weapon system. With conventional rifles, the gun barrel rests in contact with the fore-end of the gunstock, sometimes along the whole length. If the stock is manufactured from wood, environmental conditions or operational use may warp the wood, which may also cause the barrel to shift its alignment slightly over time, altering the projectile's external ballistics and thus the point of impact. Contact between the barrel and the stock also interferes with the natural frequency of the barrel, which can have a detrimental effect on accuracy especially when the barrel gets hot with repeated firing. The interference of the stock with the barrel's oscillation harmonics as the bullet passes down the bore can cause the barrel to vibrate inconsistently from shot to shot, depending on the external forces acting upon the stock at the time of the shot. Mic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thor Xm408
Thor (; from non, Þórr ) is a prominent god in Germanic paganism. In Norse mythology, he is a hammer-wielding god associated with lightning, thunder, storms, sacred groves and trees, strength, the protection of humankind, hallowing, and fertility. Besides Old Norse , the deity occurs in Old English as , in Old Frisian as ', in Old Saxon as ', and in Old High German as , all ultimately stemming from the Proto-Germanic theonym , meaning 'Thunder'. Thor is a prominently mentioned god throughout the recorded history of the Germanic peoples, from the Roman occupation of regions of , to the Germanic expansions of the Migration Period, to his high popularity during the Viking Age, when, in the face of the process of the Christianization of Scandinavia, emblems of his hammer, , were worn and Norse pagan personal names containing the name of the god bear witness to his popularity. Due to the nature of the Germanic corpus, narratives featuring Thor are only attested in Old Nors ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Firearm
A firearm is any type of gun designed to be readily carried and used by an individual. The term is legally defined further in different countries (see Legal definitions). The first firearms originated in 10th-century China, when bamboo tubes containing gunpowder and pellet projectiles were mounted on spears to make the portable fire lance, operable by a single person, which was later used effectively as a shock weapon in the Siege of De'an in 1132. In the 13th century, fire lance barrels were replaced with metal tubes and transformed into the metal-barreled hand cannon. The technology gradually spread throughout Eurasia during the 14th century. Older firearms typically used black powder as a propellant, but modern firearms use smokeless powder or other propellants. Most modern firearms (with the notable exception of smoothbore shotguns) have rifled barrels to impart spin to the projectile for improved flight stability. Modern firearms can be described by their caliber ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rifle
A rifle is a long-barreled firearm designed for accurate shooting, with a barrel that has a helical pattern of grooves ( rifling) cut into the bore wall. In keeping with their focus on accuracy, rifles are typically designed to be held with both hands and braced firmly against the shooter's shoulder via a buttstock for stability during shooting. Rifles are used extensively in warfare, law enforcement, hunting, shooting sports, and crime. The term was originally ''rifled gun'', with the verb ''rifle'' referring to the early modern machining process of creating groovings with cutting tools. By the 20th century, the weapon had become so common that the modern noun ''rifle'' is now often used for any long-shaped handheld ranged weapon designed for well-aimed discharge activated by a trigger (e.g., personnel halting and stimulation response rifle, which is actually a laser dazzler). Like all typical firearms, a rifle's projectile ( bullet) is propelled by the contained ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Match Grade
Match grade frequently refers to quality firearm parts and ammunition that are suitable for a competitive match. Sometimes it also refers to other devices and parts that are made with high precision in mind. Description In firearms, the term is used to refer to ammunition and gun parts that are designed and manufactured in such a way that they have a relatively narrow tolerance and high level of accuracy. No standards are defined for its qualification and as such it is more of a relative term. In addition to its use in shooting sports, match grade equipment is often employed by military and law enforcement sharpshooters. Thus, many gun manufacturers use the term "match grade" to describe their products. For instance, the Heckler & Koch Mark 23 weapons system is considered so specifically tooled for combat that it is match grade, one primary reason that the pistol and its components were selected by the United States Special Operations Command (SOCOM) for service. The Springfi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benchrest
Benchrest shooting is a shooting sport discipline in which accuracy and precision, high-precision rifles are rested on a table (furniture), table or countertop, bench — rather than being carried in the shooter's hands — while shooting at shooting target, paper or steel targets, hence the name "benchrest". Both the forearm (firearm component), forearm and buttstock of such a rifle are usually fully supported by bean bags, a bipod/monopod (front/rear) combination, and/or a specially designed fixture (tool), fixture device called shooting rest (which may be one- or two-piece depending on competition rules), so that the gun can remain stably pointing at the target without needing to be held by someone. When shooting, the shooter simply sits/stands comfortably behind the table/bench, operates the action (firearms), action and pulls the trigger (firearms), trigger, without needing to worry about carrying any weight of the gun. This is in contrast to other shooting disciplines, wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accurize
Accurizing is the process of improving the accuracy and precision of a gun (firearm or airgun). For firearms, accuracy is the ability to hit exactly what one is aiming at, and precision is the ability to hit the same place over and over again in a repeatable fashion. Both are the goals of accurizing, which generally concentrates on four different areas: *Usability: Enhancements that give the shooter a firmer and more controlled hold on the firearm, as well as a more consistent trigger pull. Better design ergonomics is often employed, such as adjustable buttstocks and grips with more vertical angles that are natural to the human hand and wrist (e.g. pistol grip). Spirit levels are often mounted to prevent canting, which can vary the points of impact. Weapon mounts such as bipods, monopods, benchrests, shooting sticks or simply sandbags can provide a more stable and relaxed platform for the shooter, and devices such as muzzle brakes or compensators can also be used to help co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gun Barrel
A gun barrel is a crucial part of gun-type weapons such as small firearms, artillery pieces, and air guns. It is the straight shooting tube, usually made of rigid high-strength metal, through which a contained rapid expansion of high-pressure gas(es) is used to propel a projectile out of the front end ( muzzle) at a high velocity. The hollow interior of the barrel is called the bore, and the diameter of the bore is called its caliber, usually measured in inches or millimetres. The first firearms were made at a time when metallurgy was not advanced enough to cast tubes capable of withstanding the explosive forces of early cannons, so the pipe (often built from staves of metal) needed to be braced periodically along its length for structural reinforcement, producing an appearance somewhat reminiscent of storage barrels being stacked together, hence the English name.'' A History of Warfare'' - Keegan, John, Vintage 1993. History Gun barrels are usually metal. Howev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stock (firearms)
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 b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wood Warping
Wood warping is a deviation from flatness in timber as a result of stresses and uneven shrinkage. Warping can also occur in wood considered "dry" (wood can take up and release moisture indefinitely), when it takes up moisture unevenly, or – especially – is allowed to return to its "dry" equilibrium state unevenly, too slowly, or too quickly. Many factors can contribute to wood warp: wood species, grain orientation, air flow, sunlight, uneven finishing, temperature – even cutting season and the moon's gravitational pull are taken into account in some traditions (e.g., violin making). The types of wood warping include: * bow: a warp along the length of the face of the wood * crook: a warp along the length of the edge of the wood * kink: a localized crook, often due to a knot * cup: a warp across the width of the face, in which the edges are higher or lower than the center of the wood * twist or wind: a distortion in which the two ends do not lie on the same plane. Winding s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Projectile
A projectile is an object that is propelled by the application of an external force and then moves freely under the influence of gravity and air resistance. Although any objects in motion through space are projectiles, they are commonly found in warfare and sports (for example, a thrown baseball, kicked football, fired bullet, shot arrow, stone released from catapult). In ballistics mathematical equations of motion are used to analyze projectile trajectories through launch, flight, and impact. Motive force Blowguns and pneumatic rifles use compressed gases, while most other guns and cannons utilize expanding gases liberated by sudden chemical reactions by propellants like smokeless powder. Light-gas guns use a combination of these mechanisms. Railguns utilize electromagnetic fields to provide a constant acceleration along the entire length of the device, greatly increasing the muzzle velocity. Some projectiles provide propulsion during flight by means of a rock ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
External Ballistics
External ballistics or exterior ballistics is the part of ballistics that deals with the behavior of a projectile in flight. The projectile may be powered or un-powered, guided or unguided, spin or fin stabilized, flying through an atmosphere or in the vacuum of space, but most certainly flying under the influence of a gravitational field. Gun-launched projectiles may be unpowered, deriving all their velocity from the propellant's ignition until the projectile exits the gun barrel. However, exterior ballistics analysis also deals with the trajectories of rocket-assisted gun-launched projectiles and gun-launched rockets; and rockets that acquire all their trajectory velocity from the interior ballistics of their on-board propulsion system, either a rocket motor or air-breathing engine, both during their boost phase and after motor burnout. External ballistics is also concerned with the free-flight of other projectiles, such as balls, arrows etc. Forces acting on the project ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Frequency
Natural frequency, also known as eigenfrequency, is the frequency at which a system tends to oscillate in the absence of any driving force. The motion pattern of a system oscillating at its natural frequency is called the normal mode (if all parts of the system move sinusoidally with that same frequency). If the oscillating system is driven by an external force at the frequency at which the amplitude of its motion is greatest (close to a natural frequency of the system), this frequency is called resonant frequency. Overview Free vibrations of an elastic body are called ''natural vibrations'' and occur at a frequency called the natural frequency. Natural vibrations are different from forced vibrations which happen at the frequency of an applied force (forced frequency). If the forced frequency is equal to the natural frequency, the vibrations' amplitude increases manyfold. This phenomenon is known as resonance. In a mass-spring system, with mass ''m'' and spring stiffness ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
