In the early 1850s, James Burton of the U.S. Armory at Harper’s Ferry, Virginia, improved further on the Minié bullet by eliminating the need for the iron plug and making it easier and cheaper to mass-produce. It was adapted for use by the U.S. military in 1855.
During the Civil War (1861-65), the basic firearm carried by both Union and Confederate troops was the rifle-musket and the Minié ball. The federal armory in Springfield, Massachusetts, produced a particularly effective rifle-musket that had a range of around 250 yards; some 2 million Springfield rifles were produced during the war.
The long-range accuracy of the Minié ball meant that the traditional model of warfare, when infantry and cavalry assaults could be successful, was over. Soldiers armed with a minié-loaded rifle could hide behind trees or blockades and take down approaching forces before they could get close enough to cause any damage. Weapons of an earlier age, such as the bayonet, became almost obsolete in this new kind of warfare, and the role of cavalry and field artillery was greatly reduced. Casualty figures for the American Civil War reached staggering proportions, with more than 200,000 soldiers killed and more than 400,000 wounded. The rifle-musket and the Minié bullet are thought to account for around 90 percent of these casualties.