thumb|300px|Various types of Minié balls. The four on the right are provided with [[Tamisier ball grooves for holding grease.]]

thumb|300px|[[James H. Burton's 1855 Minié ball design (.58 caliber, 500 grains) from the Harpers Ferry Armory]]

The Minié ball, or Minie ball, is a type of hollow-based bullet designed by Claude-Étienne Minié for muzzle-loaded, rifled muskets. Invented in 1849 shortly followed by the Minié rifle, the Minié ball came to prominence during 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 found 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, which themselves needed greasing, 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 with 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 cone-shaped hollow 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 gas and expanded the bullet's skirt upon firing. A higher percentage of the explosive force went toward forward projectile motion and lesser percentage toward fitting into the rifling. Burton's modified Minie ball had decreased mass and increased speed, resulting in increased energy and better range, as well as a cheaper bullet, which was used in the Crimean War and then the American Civil War. The damage to bones and resulting compound fractures were usually severe enough to necessitate amputation. A hit on a major blood vessel could also have serious and often lethal consequences.

See also

  • Cap gun
  • Caplock mechanism
  • Gun barrel
  • Gunpowder
  • Internal ballistics
  • Muzzleloader
  • Nessler ball
  • Projectile
  • Rifling
  • Tubes and primers for ammunition

References

Notes

Bibliography

  • Weaponry: The Rifle-Musket and the Minié Ball- Allan W. Howey, for the Civil War Times magazine