- Related Topics:
- ammunition
- incendiary bullet
- tracer bullet
- Minié ball
- dumdum
bullet
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What is a bullet?
A bullet is a projectile propelled from a firearm, such as a pistol, rifle, or machine gun. Caliber measures bullets based on the gun barrel's interior diameter.
Early bullets were lead balls in smoothbore weapons, ignited by black powder. Modern bullets evolved in the 19th century for rifles with rifled barrels, which spin the bullet for accuracy and range. Claude-Étienne Minié's innovation involved a soft lead bullet with a cavity and conical plug, expanding upon firing to fit the rifled bore.
Modern bullets feature a cartridge case, bullet, primer, and propellant powder. The primer ignites the propellant, launching the bullet. Materials vary: pistol bullets often use a lead-antimony alloy in a brass or copper jacket, while rifle bullets have a lead core in a steel or cupronickel jacket. Armor-piercing bullets contain a hardened-steel core. Expanding bullets, used for hunting, deform on impact to increase wounding, but are outlawed in war.
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How does ammunition work in a gun?
Ammunition contains all components needed to fire a gun, including a projectile, propellant, and primer. In small arms, complete rounds are called cartridges, and projectiles are called bullets.
When the gun's firing pin strikes the cartridge primer, the primer detonates and ignites the propellant. The rapid expansion of gases in the gun's firing chamber propels the bullet down the gun bore at high velocity. The cartridge case is left in the chamber and must be ejected.
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What are the main parts of a bullet cartridge?
A modern bullet cartridge comprises a cartridge case (a tube) that holds all the components for a complete round for use in breech-loading rifles. The bullet is affixed at the front end. At the base is the percussion cap or primer. The propellant powder sits inside the tube between these components.
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What materials are bullets usually made from?
Bullets are typically elongated metal projectiles fired from firearms, with their caliber indicating the gun barrel's bore diameter. Modern bullets evolved in the 19th century for use in rifles with rifled barrels, which impart spin to the bullet for greater accuracy and range.
Modern bullets consist of a cartridge case containing the bullet, primer, and propellant powder. Most pistol bullets are made of a lead-antimony alloy encased in brass or copper-plated steel. Rifle and machine-gun bullets feature a soft lead core encased in a harder jacket of steel or cupronickel. Armor-piercing bullets have a hardened-steel inner core. Expanding bullets, used for hunting, have an exposed soft metal nose that deforms upon impact, increasing the wound size.
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How does the bullet move when a gun is fired?
When a gun is fired, the chemical energy of a propellant converts into the kinetic energy of a projectile. The combustion gases are restrained by the shot, so the pressure rises. The shot starts to move when the pressure overcomes its resistance to motion. The pressure continues to rise for a time and then falls, while the shot is accelerated to a high velocity. The rapidly burning propellant is soon exhausted, and, in time, the shot is ejected from the muzzle. Muzzle velocities up to 15 kilometers (9 miles) per second have been achieved.
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What are some different types of bullets and their uses?
Bullets come in various types, each designed for specific purposes. Modern bullets typically feature a lead-alloy core encased in a copper alloy or mild steel jacket.
- General-purpose bullets are standard military ammunition.
- Armor-piercing bullets have hardened steel or tungsten carbide cores to penetrate armor.
- Tracer bullets contain a pyrotechnic composition that creates a visible trail during flight, aiding in aiming.
- Incendiary bullets are designed to ignite flammable materials.
- Expanding bullets deform upon impact, increasing the wound size; they are mainly used in hunting but are outlawed in war.
- Shotgun ammunition contains multiple pellets or a single slug for hunting.
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bullet, an elongated metal projectile that is fired by a pistol, rifle, or machine gun. Bullets are measured by their calibre, which indicates the interior diameter, or bore, of a gun barrel. (See bore.)
Early bullets were round lead balls that were loaded down the muzzle of smoothbore weapons and propelled by the ignition of a physically separate charge of black powder. Modern bullets developed in the 19th century for use in small arms that had rifled barrels. In these rifles, a system of helical grooves cut into the interior surface of the gun’s bore imparts spin to the bullet during its passage. The spin enables a bullet to maintain a point-forward attitude in flight, and under these conditions, an elongated bullet with a pointed tip is aerodynamically much superior to a round ball; it sustains its velocity much better in flight, thereby gaining in both accuracy and range.
Experiments with these “cylindroconoidal” bullets began about 1825, but a difficulty soon arose. The bullets had to fit tightly in the barrel, and it proved difficult to load a tight-fitting bullet in a muzzle-loading gun. The solution was found by Claude-Étienne Minié of France, who in 1849 developed a soft lead bullet with a cavity in its base into which a conical plug was fitted. The bullet’s diameter was small enough that it slid freely down the gun bore, and the sudden inflammation of the propellant charge upon firing drove the conical plug forward to expand the lead bullet tightly into the grooves of the rifled bore.
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By the 1860s, percussion caps, which detonate upon being struck a sharp blow by the firing pin of a gun, had been incorporated into a metal cartridge case containing all the components for a complete round that could be used in breech-loading rifles. In the 1880s, the introduction of nitrocellulose, or guncotton, in place of black powder as the propellant charge provided the final element for the modern bullet.
A modern bullet consists of a tube (the cartridge case) with the bullet affixed at the front end, the percussion cap or primer at the base, and the propellant powder contained in the tube between. Upon being struck by the gun’s firing pin, the percussion cap detonates and ignites the propellant; the resulting rapid expansion of gases in the gun’s closed firing chamber propels the bullet forward at high velocity down the bore. The cartridge case is left in the chamber and must be ejected by mechanical means.
Most pistol bullets are made of a lead-antimony alloy encased in a soft brass or copper-plated soft steel jacket. In rifle and machine-gun bullets, a soft core of lead is encased in a harder jacket of steel or cupronickel. Armour-piercing bullets have a hardened-steel inner core. Expanding bullets, used in game hunting and long outlawed in war, are made with an exposed nose of soft metal, which will push back into the jacketed portion to deform it on impact, enlarging the wound and increasing the shock of the impact. See also ammunition.