A bullet is a solid projectile propelled by a firearm or air gun and is normally made from metal (usually lead). A bullet (in contrast to a shell) does not contain explosives, and damages the intended target solely by imparting kinetic energy upon impact.
The word "bullet" is sometimes erroneously used to refer to the combination of bullet, case, gunpowder and primer more properly known as a cartridge or round; the Oxford English Dictionary definition of a bullet is "a projectile of lead ... for firing from a rifle, revolver etc." In contrast, bullets for air guns are not part of a cartridge.
The first bullets
The history of bullets parallels the history of firearms. It`s no surprise that advances in one resulted from or precipitated advances in the other. Originally, bullets were metallic or stone balls placed in front of an explosive charge of gun powder at the end of a closed tube. As firearms became more technologically advanced, from 1500 to 1800, bullets changed very little. They remained simple round lead balls, called rounds, differing only in their diameter.
The development of the hand culverin and matchlock arquebus brought about the use of cast lead balls as projectiles. "Bullet" is derived from the French word "boulette" which roughly means "little ball". The original musket bullet was a spherical lead ball two sizes smaller than the bore, wrapped in a loosely-fitted paper patch which served to hold the bullet in the barrel firmly upon the powder. (Bullets that were not firmly upon the powder upon firing risked causing the barrel to explode, with the condition known as a "short start".) The loading of muskets was, therefore, easy with the old smooth-bore Brown Bess and similar military muskets. The original muzzle-loading rifle, on the other hand, with a more closely fitting ball to take the rifling grooves, was loaded with difficulty, particularly when the bore of the barrel was dirty from previous firings ("fouled"). For this reason, early rifles were not generally used for military purposes. Early rifle bullets required cloth patches to grip the rifling grooves, and to hold the bullet securely against the powder.
The first half of the nineteenth century saw a distinct change in the shape and function of the bullet. In 1826, Delirque, a French infantry officer, invented a breech with abrupt shoulders on which a spherical bullet was rammed down until it caught the rifling grooves. Delirque`s method, however, deformed the bullet and was inaccurate.
Among the first conical bullets were designed by Captain John Norton of the British Army in 1823. Norton`s bullet had a hollow base which expanded under pressure to catch the rifling grooves at the moment of being fired; the British Board of Ordnance rejected it because spherical bullets had been in use for the last 300 years.
Renowned English gunsmith William Greener invented the Greener bullet in 1836. It was very similar to Norton`s bullet except that the hollow base of the bullet was fitted with a wooden plug which more reliably forced the base of the bullet to expand and catch the rifling. Tests proved that Greener`s bullet was extremely effective but it too was rejected for military use because, being two parts, it was judged as being too complicated to produce.
The soft lead bullet that came to be known as the Minié ball, (or minnie ball) was first introduced in 1847 by Claude Étienne Minié (1814? - 1879), a captain in the French Army. It was nearly identical to the Greener bullet. As designed by Minié, the bullet was conical in shape with a hollow cavity in the rear, which was fitted with a little iron cap instead of a wooden plug. When fired, the iron cap would force itself into the hollow cavity at the rear of the bullet, thereby expanding the sides of the bullet to grip and engage the rifling. In 1855, the British adopted the Minié ball for their Enfield rifles.
It was in the American Civil War, however, that the Minié ball first saw widespread use. Roughly 90% of the battlefield casualties in this war were caused by Minié balls fired from rifles.
.270 ammunition. Left to Right: 100 grain - Hollow Point, 115 grain FMJBT, 130 grain Soft point, 150 grain round nose.
.303 inch centrefire, FMJ rimmed ammunitionBetween 1854 and 1857, Sir Joseph Whitworth conducted a long series of rifle experiments, and proved, among other points, the advantages of a smaller bore and, in particular, of an elongated bullet. The Whitworth bullet was made to fit the grooves of the rifle mechanically. The Whitworth rifle was never adopted by the government, although it was used extensively for match purposes and target practice between 1857 and 1866, when it was gradually superseded by Metford`s.
About 1862 and later, W. E. Metford had carried out an exhaustive series of experiments on bullets and rifling, and had invented the important system of light rifling with increasing spiral, and a hardened bullet. The combined result of the above inventions was that in December 1888 the Lee-Metford small-bore (0.303") rifle, Mark I, (photo of cartridge on right) was finally adopted for the British army. The Lee-Metford was the predecessor of the Lee-Enfield.
The modern bullet
The next important change in the history of the rifle bullet occurred in 1883, when Major Rubin, director of the Swiss Laboratory at Thun, invented the copper jacketed bullet; an elongated bullet with a lead core in a copper envelope or jacket.
The copper jacketed bullet allows much higher muzzle velocities than lead alone, as copper has a much higher melting point, greater specific heat capacity, and is harder. Lead bullets fired at high velocity may suffer surface melting due to hot gases behind and friction with the bore.
European advances in aerodynamics led to the pointed `spitzer` bullet. By the beginning of the twentieth century, most world armies had begun to transition to spitzer bullets. These bullets flew for greater distances more accurately and carried more energy with them. Spitzer bullets combined with machine guns increased the lethality of the battlefield exponentially.
The final advancement in bullet shape occurred with the development of the ‘boat tail’ which is a streamlined base for spitzer bullets. A vacuum is created when air strata moving at high speed passes over the end of a bullet. The streamlined boat tail design aims to eliminate this drag-inducing vacuum by allowing the air to flow alongside the surface of the tapering end, thus eliminating the need for air to turn around the 90-degree angle normally formed by the end of shaped bullets. The resulting aerodynamic advantage is currently seen as the optimum shape for rifle technology. The spitzer boat-tailed bullet ( Balle "D" )was first introduced as standard ammunition in a military rifle in 1901, for the French Lebel Mle 1886 service weapon.
AP - Armor Piercing
BT - Boat Tail
CP - Cone Point
FMJ - Full Metal Jacket
GLASER Safety Slug
JFP - Jacket Flat Point
JHP - Jacket HollowPoint
JSP - Jacket SoftPoint
JRN - Jacket Round Nose
Hydrashock - JHP bullet with rod for improved expansion
L - Lead
LHP - Lead HollowPoint
LRN - Lead RoundNose
LSW - Lead SemiWadcutter
LWC - Lead WadCutter
SJ ESC* (*acronym to designate special armor-piercing Semi-Jacketed Exposed Steel Core bullets, designed to deal with modern army-style bulletproof jackets, made of kevlar and titanium or composite armor plates. Those bullets has aluminium jacket with hardened steel core, exposed and pointed at the nose of the bullet.)
THV - Tres Haute Vitesse