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Bullet Trap
A bullet trap (or pellet trap when used specifically for air guns) is a device to stop and collect projectiles fired at a shooting range to prevent overpenetrations and stray shots. Bullet traps typically use friction, impact or gradual deceleration to stop bullets. The bullet trap may also provide means to recycle bullet materials and/or prevent release of toxic heavy metals (such as lead dust from fragmented bullets) from the shooting range. Some bullet traps include a negative-pressure system to filter dust from air within the impact zone and/or capture area. Deceleration traps Deceleration-type bullet traps direct bullets into a helical or circular chamber in which the bullet will slide against the curved chamber wall until it gradually loses velocity from friction and drops to the bottom of the chamber, where it can be later collected. For use with multiple firing positions, the helical chamber often resembles a horizontal pipe, into which bullets are directed by uppe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bullet Trap
A bullet trap (or pellet trap when used specifically for air guns) is a device to stop and collect projectiles fired at a shooting range to prevent overpenetrations and stray shots. Bullet traps typically use friction, impact or gradual deceleration to stop bullets. The bullet trap may also provide means to recycle bullet materials and/or prevent release of toxic heavy metals (such as lead dust from fragmented bullets) from the shooting range. Some bullet traps include a negative-pressure system to filter dust from air within the impact zone and/or capture area. Deceleration traps Deceleration-type bullet traps direct bullets into a helical or circular chamber in which the bullet will slide against the curved chamber wall until it gradually loses velocity from friction and drops to the bottom of the chamber, where it can be later collected. For use with multiple firing positions, the helical chamber often resembles a horizontal pipe, into which bullets are directed by uppe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ISSF Shooting Events
The International Shooting Sport Federation recognizes several shooting events, some of which have Olympic status. They are divided into four disciplines: rifle, pistol, shotgun and running target. The main distinctions between different rifle events are the distances to the target and the shooting positions used. For the other disciplines, the position is always standing, and changes include limits to shooting times and different types of targets. The present events Discontinued events Due to the ISSF, some Olympic events have been discontinued in the past. In total, Forty-five ISSF events have been discontinued. Common principles All ISSF shooting events consist of ''precision'' shooting in the sense that only the position of the shot on the target determines the result, not the time used to produce that shot (provided the time was within the set constraints, of course). This separates them from International Practical Shooting Confederation events and other kinds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Environmental Protection Agency
The Environmental Protection Agency (EPA) is an independent executive agency of the United States federal government tasked with environmental protection matters. President Richard Nixon proposed the establishment of EPA on July 9, 1970; it began operation on December 2, 1970, after Nixon signed an executive order. The order establishing the EPA was ratified by committee hearings in the House and Senate. The agency is led by its administrator, who is appointed by the president and approved by the Senate. The current administrator is Michael S. Regan. The EPA is not a Cabinet department, but the administrator is normally given cabinet rank. The EPA has its headquarters in Washington, D.C., regional offices for each of the agency's ten regions and 27 laboratories. The agency conducts environmental assessment, research, and education. It has the responsibility of maintaining and enforcing national standards under a variety of environmental laws, in consultation with state, tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vehicle Tire
A tire (American English) or tyre (British English) is a ring-shaped component that surrounds a wheel's rim to transfer a vehicle's load from the axle through the wheel to the ground and to provide traction on the surface over which the wheel travels. Most tires, such as those for automobiles and bicycles, are pneumatically inflated structures, which also provide a flexible cushion that absorbs shock as the tire rolls over rough features on the surface. Tires provide a footprint, called a contact patch, that is designed to match the weight of the vehicle with the bearing strength of the surface that it rolls over by providing a bearing pressure that will not deform the surface excessively. The materials of modern pneumatic tires are synthetic rubber, natural rubber, fabric, and wire, along with carbon black and other chemical compounds. They consist of a tread and a body. The tread provides traction while the body provides containment for a quantity of compressed air ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Railway Tie
A railroad tie, crosstie (American English), railway tie ( Canadian English) or railway sleeper (Australian and British English) is a rectangular support for the rails in railroad tracks. Generally laid perpendicular to the rails, ties transfer loads to the track ballast and subgrade, hold the rails upright and keep them spaced to the correct gauge. Railroad ties are traditionally made of wood, but prestressed concrete is now also widely used, especially in Europe and Asia. Steel ties are common on secondary lines in the UK; plastic composite ties are also employed, although far less than wood or concrete. As of January 2008, the approximate market share in North America for traditional and wood ties was 91.5%, the remainder being concrete, steel, azobé (red ironwood) and plastic composite. Tie spacing may depend on the type of tie, traffic loads and other requirements, for example 2640 concrete ties per mile on North American mainline railroads to 2112 timber ties per mil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gun Range 100 Yards
A gun is a ranged weapon designed to use a shooting tube (gun barrel) to launch projectiles. The projectiles are typically solid, but can also be pressurized liquid (e.g. in water guns/cannons, spray guns for painting or pressure washing, projected water disruptors, and technically also flamethrowers), gas (e.g. light-gas gun) or even charged particles (e.g. plasma gun). Solid projectiles may be free-flying (as with bullets and artillery shells) or tethered (as with Taser guns, spearguns and harpoon guns). A large-caliber gun is also called a ''cannon''. The means of projectile propulsion vary according to designs, but are traditionally effected pneumatically by a high gas pressure contained within the barrel tube, produced either through the rapid exothermic combustion of propellants (as with firearms), or by mechanical compression (as with air guns). The high-pressure gas is introduced behind the projectile, pushing and accelerating it down the length of the tube, impart ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ricochet
A ricochet ( ; ) is a rebound, bounce, or skip off a surface, particularly in the case of a projectile. Most ricochets are caused by accident and while the force of the deflection decelerates the projectile, it can still be energetic and almost as dangerous as before the deflection. The possibility of ricochet is one of the reasons for the common firearms safety rule "Never shoot at a flat, hard surface." Ricochets can occur with ''any'' caliber, but short or round ricocheting bullets may not produce the audible whine caused by tumbling irregular shapes. Ricochets are a hazard of shooting because, for as long as they retain sufficient velocity, ricocheting bullets or bullet fragments may cause collateral damage to animals, objects, or even the person who fired the shot. Variables Ricochets occur when a bullet or bullet fragment is deflected by an object rather than penetrating and becoming embedded in that object. Ricochet behavior may vary with bullet shape, bullet material, s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deflection (physics)
In physics, deflection is a change in a moving object's velocity, hence its trajectory, as a consequence of contact (collision) with a surface or the influence of a non-contact force field. Examples of the former include a ball bouncing off the ground or a bat; examples of the latter include a beam of electrons used to produce a picture, or the relativistic bending of light due to gravity. Deflective efficiency An object's deflective efficiency can never equal or surpass 100%, for example: *a mirror will never reflect exactly the same amount of light cast upon it, though it may concentrate the light which is reflected into a narrower beam. *on hitting the ground, a ball previously in free-fall (meaning no force other than gravity acted upon it) will never bounce back up to the place where it first started to descend. This transfer of some energy into heat or other radiation is a consequence of the theory of thermodynamics, where, for every such interaction, some energy mus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rimfire Ammunition
Rimfire ammunition is a type of firearm metallic cartridge whose primer is located within a hollow circumferential rim protruding from the base of its casing. When fired, the gun's firing pin will strike and crush the rim against the edge of the barrel breech, sparking the primer compound within the rim, and in turn ignite the propellant within the case. Invented in 1845, by Louis-Nicolas Flobert, the first rimfire metallic cartridge was the .22 BB Cap (a.k.a. 6mm Flobert) cartridge, which consisted of a percussion cap with a bullet attached to the top. While many other different cartridge priming methods have been tried since the 19th century, only rimfire and the later centerfire cartridges survive to the present day with regular usages. The .22 Long Rifle rimfire cartridge, introduced in 1887, is by far the most common ammunition in the world today in terms of units sold. Characteristics Rimfire ammunition is so named because the firing pin strikes and crushes the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Department Of Energy
The United States Department of Energy (DOE) is an executive department of the U.S. federal government that oversees U.S. national energy policy and manages the research and development of nuclear power and nuclear weapons in the United States. The DOE oversees the U.S. nuclear weapons program, nuclear reactor production for the United States Navy, energy-related research, and domestic energy production and energy conservation. The DOE was created in 1977 in the aftermath of the 1973 oil crisis. It sponsors more physical science research than any other U.S. federal agency, the majority of which is conducted through its system of National Laboratories. The DOE also directs research in genomics, with the Human Genome Project originating from a DOE initiative. The department is headed by the Secretary of Energy, who reports directly to the president of the United States and is a member of the Cabinet. The current Secretary of Energy is Jennifer Granholm, who has served ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centrefire
Two rounds of .357 Magnum, a centerfire cartridge; notice the circular primer in the center A centerfire cartridge is a firearm metallic cartridge whose primer is located at the center of the base of its casing (i.e. "case head"). Unlike rimfire cartridges, the centerfire primer is typically a separate component seated into a recessed cavity (known as the ''primer pocket'') in the case head and is replaceable by reloading. Centerfire cartridges have supplanted the rimfire variety in all but the smallest cartridge sizes. The majority of today's handguns, rifles, and shotguns use centerfire ammunition, with the exception of a few .17 caliber, .20 caliber, and .22 caliber handgun and rifle cartridges, small-bore shotgun shells (intended for pest control), and a handful of antique (and mostly obsolete) cartridges. History An early form of centerfire ammunition, without a percussion cap, was invented between 1808 and 1812 by Jean Samuel Pauly. This was also the first fully in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
