German gunmakers in the 16th century first developed guns with rifling. Like all early guns, the rifle was loaded through the muzzle, into which powder and ball were inserted and tamped into place with a ramrod. The rifle was slower to load than the smoothbore, because it required tighter-fitting ammunition, either in the form of a larger-size ball or a ball wrapped in a greased patch. Sportsmen began using rifles, but armies, whose tactics in those days depended more on rapid rate of fire than on accuracy, found them unsuitable.

In the 1730's German gunmakers in Pennsylvania began producing the Kentucky rifle, so called because it was designed to be used on the Kentucky frontier. Its extra-long barrel (51 to 77 inches [130 to 196 cm]) and relatively small caliber (about .45, or 11 mm) made it the most accurate rifle of its day. The gunpowder was ignited by sparks that were struck when the hammer, containing a piece of flint, was released. Such a weapon was called a flintlock. The Kentucky rifle was used in the French and Indian War and the American Revolutionary War by militia and irregular troops.

Gunmakers worked to find a way to speed the loading of rifles, and during the 18th and early 19th centuries various armies experimented with breechloaders. During the American Revolution, the British briefly tried out the breechloaders invented by Patrick Ferguson. John H. Hall perfected a breechloader that was adopted by some U.S. Army troops in 1819. A Hall rifle carbine was one of the first in which the flintlock system of ignition was replaced by the percussion system, which used a chemical-filled cap that exploded upon being struck. In 1841 the Prussian army adopted a breechloader, invented by Johann Dreyse and known as the “needlegun” for the long slender pin used to strike its percussion cap. Defects in the early breechloaders prevented their complete acceptance.

In 1849 Claude tienne Mini invented an elongated bullet (the Mini ball) whose base would expand (through the force of the explosion) to fit the rifling. The loose-fitting bullet allowed fast loading, and most armies switched to rifles. In the United States, the standard infantry weapon of the Civil War was the musket-rifle, a muzzle-loading percussion weapon that used the Mini ball.

Meanwhile, in 1848 Christian Sharps had perfected a breechloader. It was used in limited numbers in the Civil War and was a popular buffalo gun on the frontier. The Colt, Spencer, Henry, and other breech-loading repeater rifles were used by Civil War cavalry troops. At the close of the war, the U.S. Army adopted as its standard infantry weapon a single-shot breechloader. Gradually the breechloader replaced muzzleloaders in all armies.

The repeating rifle, including Winchester's 1873 and the Remington, was popular among sportsmen and on the American frontier. Rifles designed especially for sportsmen began to appear in the late 1800's; many were refinements of military rifle designs. The U.S. Army first adopted a repeater as the standard infantry weapon in 1894. It was the .30-caliber (7.62-mm) bolt-action Krag-jgensen, invented in Norway, and used in the Spanish-American War. This was superseded by the United States Magazine Rifle, Model of 1903 (commonly called the “Springfield” or the “ '03”), which was modified in 1906 to take a slightly different cartridge. Sporting guns using this cartridge are said to be of caliber .30-06. After World War I the Springfield and the German infantry rifle, the Mauser M-98, formed the basis of many sporting and target rifles.

In 1936 the U.S. Army adopted the semiautomatic .30-caliber M-1 rifle developed by J. C. Garand at the Springfield Armory. It was the standard infantry weapon of World War II and the Korean War. The 7.62-mm (.308-caliber) automatic M-14 rifle was adopted by the United States in 1957.

Meanwhile, in World War II, the Germans developed a new kind of rifle, the Sturmgewehr StG-44 ("assault rifle"), which had a short range, but had the advantage of using short, lightweight bullets and having fully automatic fire. After the war, other countries began developing similar rifles. In 1947, the Soviet Union introduced the 7.62-mm AK-47, which eventually was adopted by more armies than any other rifle. In the late 1970's the Soviets replaced the AK-47 with the 5.45-mm AK-74. In 1964, the United States replaced the M-14 with the 5.56-mm M-16.

Armies also began developing new sniper rifles, because snipers found automatic-loading rifles less suitable than the earlier bolt-action rifles. Bolt-action sniper rifles introduced since the mid-1980's include the United States armed forces' 7.62-mm M-24 and .50 caliber M-82A1A.