|
22 Long Rifle
The .22 long rifle, also known as the .22 LR or 5.7×15mmR, is a long-established variety of .22 caliber rimfire ammunition originating from the United States. It is used in a wide range of firearms including rifles, pistols, revolvers, and submachine guns. In terms of units sold, it is by far the most common ammunition that is manufactured and sold in the world. Common uses include hunting and shooting sports. Ammunition produced in .22 long rifle is effective at short ranges, has little recoil, and is inexpensive to purchase. These qualities make it ideal for plinking and marksmanship training. History American cartridge 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, render ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 contiguous states border Canada to the north and Mexico to the south, with the semi-exclave of Alaska in the northwest and the archipelago of Hawaii in the Pacific Ocean. The United States asserts sovereignty over five Territories of the United States, major island territories and United States Minor Outlying Islands, various uninhabited islands in Oceania and the Caribbean. It is a megadiverse country, with the world's List of countries and dependencies by area, third-largest land area and List of countries and dependencies by population, third-largest population, exceeding 340 million. Its three Metropolitan statistical areas by population, largest metropolitan areas are New York metropolitan area, New York, Greater Los Angeles, Los Angel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heeled Bullet
A heeled bullet is a bullet that is necked down at its base to allow a projectile the full internal diameter of a gun barrel to fit in a cartridge case of the same or narrower dimension. Heeled bullets mostly disappeared with the advent of smokeless powder cartridges, though older rimfire designs, such as the .22 caliber cartridges, still use heeled bullets, and many cartridges that date back to the black powder era still reflect their heeled bullet origins in their caliber designations. More powerful smokeless powder allowed the use of smaller, non-heeled projectiles in existing caliber guns. Two examples are a ".38 caliber" firearm actually shooting bullets of diameter, and a ".44 caliber" bullets of diameter. This legacy of historic heeled bullets is the cause of confusion among many shooting enthusiasts over the actual physical diameters of the bullets they fire. Reasons for change The heeled bullet design has many advantages, mainly when coupled with the straight or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Squirrel
Squirrels are members of the family Sciuridae (), a family that includes small or medium-sized rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrels. Squirrels are indigenous to the Americas, Eurasia, and Africa, and were introduced by humans to Australia. The earliest known fossilized squirrels date from the Eocene epoch, and among other living rodent families, the squirrels are most closely related to the mountain beaver and dormice. Etymology The word ''squirrel'', first attested in 1327, comes from the Anglo-Norman which is from the Old French , the reflex of a Latin language">Latin word , which was taken from the Ancient Greek word (; from ) 'shadow-tailed', referring to the long bushy tail which many of its members have. ''Sciurus'' is also the name of one of its genuses. The native Old English language, Old English word for the squirrel, , only survived into Middle Eng ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shock Wave
In physics, a shock wave (also spelled shockwave), or shock, is a type of propagating disturbance that moves faster than the local speed of sound in the medium. Like an ordinary wave, a shock wave carries energy and can propagate through a medium, but is characterized by an abrupt, nearly discontinuous, change in pressure, temperature, and density of the medium. For the purpose of comparison, in supersonic speed, supersonic flows, additional increased expansion may be achieved through an expansion fan, also known as a Prandtl–Meyer expansion fan. The accompanying expansion wave may approach and eventually collide and recombine with the shock wave, creating a process of destructive interference. The sonic boom associated with the passage of a supersonic aircraft is a type of sound wave produced by Wave interference, constructive interference. Unlike solitons (another kind of nonlinear wave), the energy and speed of a shock wave alone dissipates relatively quickly with distan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supersonic Speed
Supersonic speed is the speed of an object that exceeds the speed of sound (Mach number, Mach 1). For objects traveling in dry air of a temperature of 20 °C (68 °F) at sea level, this speed is approximately . Speeds greater than five times the speed of sound (Mach 5) are often referred to as hypersonic. Flights during which only some parts of the air surrounding an object, such as the ends of rotor blades, reach supersonic speeds are called transonic. This occurs typically somewhere between Mach 0.8 and Mach 1.2. Sounds are traveling vibrations in the form of pressure waves in an elastic medium. Objects move at supersonic speed when the objects move faster than the speed at which sound propagates through the medium. In gases, sound travels longitudinally at different speeds, mostly depending on the molecular mass and temperature of the gas, and pressure has little effect. Since air temperature and composition varies significantly with altitude, th ... [...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] |
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 projectile ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Shooting Sports Foundation
The National Shooting Sports Foundation (NSSF) is an American national trade association for the firearms industry that is based in Newtown, Connecticut. Formed in 1961, the organization has more than 8,000 members: The NSSF helps write safety and instruction standards. The NSSF sponsors the annual Shooting Hunting and Outdoor Trade Show, the (SHOT Show).The History of The National Shooting Sports Foundation (NSSF) NSSF.org, Retrieved December 20, 2012. The NSSF has advocated in favor of Gun politics in the United States, gun rights, including arguing against limits on high capacity magazines and the broad use of the term "assault weapon". It has also supported legislation allowing concealed carry and has offered proposals to prohibit the United States Enviro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
M1911
The Colt M1911 (also known as 1911, Colt 1911, Colt .45, or Colt Government in the case of Colt-produced models) is a single-action, recoil-operated, semi-automatic pistol chambered primarily for the .45 ACP cartridge. History Early history and adaptations The M1911 pistol originated in the late 1890s as the result of a search for a suitable self-loading (or semi-automatic) pistol to replace the variety of revolvers in service at the time. The United States was adopting new firearms at a phenomenal rate; several new pistols and two all-new service rifles ( M1892/96/98 Krag and M1895 Navy Lee), as well as a series of revolvers by Colt and Smith & Wesson for the Army and Navy, were adopted just in that decade. The next decade would see a similar pace, including the adoption of several more revolvers and an intensive search for a self-loading pistol that would culminate in the official adoption of the M1911 after the turn of the decade. Hiram S. Maxim had designed a self- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
