Gun barrel

The barrel of a gun or other firearm is the tube, usually metal, through which a controlled explosion is released in order to propel a projectile out of the end at great speed.

The first guns were made in a time where metallurgy was not quite what it is today, so the pipe needed to be braced periodically along its length, producing an appearance somewhat reminiscent of a barrel.

Another explanation, tied to etymology, states that many very first firearms barrels where in fact realized, during the 12-13 century, using small storage barrels with their usual metal rings reinforced by leather, hence the barrel name. In fact a set of old French words, some of them staying in modern French, were used as root words for various English firearms (and storage barrels) -related terms. The old French gonne (pronounced by a French speaker it sounds approximately as gun does when pronounced by an English speaker) was a small barrel used on merchant and military ships. Likewise a baril was, as soon as in approx 1320 (used in Du Chevalier au barisel), and remains now, a big barrel. Moreover the big Tun English barrel is, as stated in Ton, the French old and contemporary tonne barrel.

Construction

Modern day gun barrels are sophisticated in their construction and makeup. A gun barrel must be able to hold in the expanding gas produced by the propellant to ensure that optimum muzzle velocity is attained by the bullet or shell as it is being pushed out by the expanding gas(es). Early firearms were mostly muzzle loading (loaded from the mouth rather than the breech), which tends to be a slow and complicated procedure, resulting in a low rate of fire. Breech loading provided a higher rate of fire, but early breech loading guns lacked an effective way of sealing the escaping gases that leaked from the back end of the barrel; resulting in a lower muzzle velocity. This problem was solved with the use of rubber, an effective material that can be used to seal the breech.

Gun barrels are mostly of metal construction. The early Chinese, the inventors of gunpowder, used bamboo, a naturally tubular wood, as the first barrels in gunpowder projectile weapons. Early European guns were made of wrought iron, usually several bands of the metal arranged around circular wrought iron rings and then welded into a hollow cylinder. The Chinese were the first to master cheap cast-iron cannon barrels. Bronze and brass were favoured by gunsmiths, due to them being easy to cast and their ability to stand corrosion created from the firing of their gunpowder charges. Modern gun barrels are of nickel and steel alloys, which are made to withstand the tension created by the rapidly expanding gases of the cartridge as well as resist corrosion. Tamper gun barrels compress-shape their munition as it goes down the barrel, creating a smaller cross-section on the bullet, which reduces air friction as it flies through the air while maintaining its muzzle velocity. As metallurgy advances, barrels can be made smaller and lighter without undermining their strength in holding the explosive gases as the firearm fires. Early cannons were hugely thick for the calibre that they fired. Barrels become weaker after every volley they fire, hence they have a limited service life. Early manufacturing defects (such as air bubbles trapped in the barrel) key into many gun explosions, in which the expanding gases become to much for the barrel, causing it to rupture and explode in deadly fragments of metal.

Smallbore

Generally a the term "smallbore" refers to rifles or pistols in a caliber .22 (5.56mm) rimfire cartridge. Rifles, revolvers and semi-auto pistols in caliber .22 rimfire are popular all over the world for small game hunting and casual target shooting. Rifles and pistols that shoot centerfire cartridges in caliber 5.56 and 6mm are refered to as "highpower" cartridge arms.

See also

• kissing the gunner's daughter (i.e. taking a spanking while bending over a gun barrel)
• Rifling
• Smoothbore
• Slug barrel
• Cannon
• Pistol-whipping