Firearm - Background

Background

Beginning around 700 A.D., scientists and inventors in Ancient China developed different grades of gunpowder and different types of firearms, including single-shot smooth-bore fire lances, multi-barreled guns, multiple-launch artillery rockets and the first cannon in the world made from cast bronze. Several centuries later, in late Dark Age Europe, the term "firearm" was used in Old English to denote the arm in which the match was held that was used to light the touch hole on the hand cannon. The term was a variation on the contemporary terms of bow arm and drawing arm still used in archery. Due to the effects of firing the ordnance (barrel) at the time, the gunner had to be located somewhat behind the weapon, steadying brace with the other hand. Eventually, the term "fire arm" became synonymous with the weapons themselves.

Although the modern term "gun" is often used as a synonym for firearm, in specialist or military use it has a restricted sense referring only to an artillery piece with a relatively high muzzle velocity, such as a field gun, a tank gun, or a gun used in the delivery of naval gunfire; or in sporting use for a shotgun. Machine guns fire small-caliber ammunition (generally 12.7 mm (0.50 in) (.50 Cal) or smaller), and many machine guns are crew-served infantry support weapons, requiring the services of more than one crewman, just like artillery guns. Hand-held firearms such as rifles, carbines, pistols and other small firearms, are rarely called "guns" in the restricted sense among specialists. Artillery guns are much larger than these firearms, mounted on movable carriages, having bores of up to 18 inches (46 cm) and weighing up to many tons. Generally, an automatic firearm designed for a single user is referred to as an automatic rifle. Other terms, including "firearm" itself, have been defined in specialized ad hoc ways by various legislation; air weapons, for example, are sometimes so classified.

Since their inception firearms have become widely used. Modern warfare since the late Renaissance has relied upon firearms, with wide-ranging effects on military history and history in general. This changed the nature of combat and of military units.

For handguns and long guns, the projectile is a bullet or, in historical hand cannons, a shot. The shot was initially made from lead already used as ammunition for the slings, and begun with the ballistic shape of a modern bullet, but was rapidly replaced by the cast iron ball. The projectile is fired by the burning of the propellant; small arms projectiles very rarely contain explosives, and such ammunition is banned by the Hague Conventions of 1899 and 1907. The use of expanding (e.g. hollow-point) small-arms ammunition in warfare is also banned by the Convention for similar reasons (it aggravates the severity of wounds from small-arms fire). Explosive shells replaced solid ammunition artillery from the nineteenth century.

Until the mid-19th century, projectiles and propellant (black powder) were generally separate components used in a muzzle-loading firearm such as a rifle, pistol, or cannon. Sometimes for convenience a suitable amount of powder and a bullet were wrapped in a paper package, known as a cartridge. This evolved into the form of a tubular metal casing enclosing a primary igniter (primer) and the powder charge, with the projectile press-fit into the end of the casing opposite the primer. Cartridge ammunition was widely adopted, and as of World War I it had become the primary form of ammunition for small arms, tanks, and lighter artillery. Mortars use a similar concept of encapsulation; however the projectile and casing are generally a single piece that is launched from the mortar. Some short-range naval guns use cased ammunition, but many battleship and cruiser main guns use a shell and separate bagged powder measures, which are selected according to the desired ballistic path.

A distinction is sometimes made between the projectile itself as the weapon and the firearm as a weapons platform. In some cases, the firearm can be used directly as a weapon without firing a projectile, although this is virtually always a secondary method of attack used in close combat. For example, arms such as rifles, muskets, and occasionally submachine guns can have bayonets affixed to them, becoming in effect spears or pikes. With some notable exceptions, the stock of a long gun can be used as a club. It is also possible to strike someone with the barrel of a firearm or grasp it by the barrel or grip and strike someone with the butt, which is informally called "pistol-whipping".

A problem for firearms is the accumulation of waste products from the partial combustion of propellants, metallic residue from the bullet itself, and small flecks of the cartridge case, collectively known as fouling or gunshot residue. These waste products can interfere with the internal functions of the firearm. As a result, regularly used firearms must periodically be partially disassembled, cleaned and lubricated to ensure the firearm's reliability.

Firearms may sometimes be referred to as small arms. Small arms are firearms which can be carried by a single individual. According to international conventions governing the laws of war, small arms are defined (with some exceptions) as firearms which fire a projectile not in excess of 15 mm (0.60 inches) in diameter. Small arms are aimed visually at their targets by hand using either iron sights or optical sights. The accurate range of pistols is generally limited to 50 metres (55 yd), while most rifles are accurate to 500 metres (550 yd) using iron sights, or longer ranges using optical sights. (Firearm rounds may be dangerous or lethal well beyond their accurate range; minimum distance for safety is much greater than specified range.) Some purpose-built sniper rifles are accurate to ranges of more than 2,000 metres (2,200 yd). A successful sniper attack has been made from slightly more than 1.5 mi (2.4 km).

The manufacture of firearms is a large industry. According to the National Shooting Sports Foundation (N.S.S.F.), a trade association for the US firearms industry, all economic activity from firearm manufacturing, distribution, and other ancillary activities totaled US$27.8 billion in 2010 in the United States.