The Minié ball or Minie ball, is a type of hollow-based bullet designed by Claude-Étienne Minié, inventor of the French Minié rifle, for muzzle-loading rifled muskets. It was invented in 1847 and came to prominence in the Crimean War and the American Civil War, where it was found to inflict significantly more serious wounds than earlier round musket balls. Both the American Springfield Model 1861 and the British Pattern 1853 Enfield rifled muskets, the most common weapons used during the American Civil War, used the Minié ball. Rifling, the addition of spiral grooves inside a gun barrel, imparts a stabilizing spin to a projectile for better external ballistics, greatly increasing the effective range and accuracy of the gun. Before the introduction of the Minié ball, balls had to be rammed down the barrel, sometimes with a mallet, because gunpowder residue would foul a rifled bore after a relatively small number of shots, requiring frequent cleaning of the gun. The development of the Minié ball was significant because it was the first projectile type that could be made a loose enough fit to easily slide down the barrel of a rifled long gun, yet maintain good accuracy during firing due to obturation by expansion of the bullet's base when fired. Designs The Minié ball is a cylindro-conoidal bullet with grease-filled cannelures on its exterior and a conical concavity in its base. Minié designed the bullet with a small iron plug, and lead skirting that would expand under the pressure of gunpowder deflagration causing the bullet to obturate, and grip the rifling grooves. This maximized muzzle velocity by creating a good bullet-to-bore seal with minimal pressure loss. A precursor to the Minié ball was created in the 1830s by French Army captains Montgomery and Henri-Gustave Delvigne. Their design was made to allow rapid muzzle loading of rifles, an innovation that brought about the widespread use of the rifle rather than the smoothbore musket as a mass battlefield weapon. Delvigne had invented a ball that could expand upon ramming to fit the grooves of a rifle in 1826. The cylindro-conoidal ball design had been proposed in 1832 by Captain John Norton, but had not been adopted. Captain James H. Burton, an armorer at the Harpers Ferry Armory, developed a major improvement on Minié's design when he added a deep conical cavity at the base of the ball, which more efficiently filled up with