This lead projectile still has remnants of the dried, chalky clay-like dirt it was found in. It is a Minié ball (minie ball) and is a type of muzzle-loading, spin-stabilizing rifle bullet named after its co-developer, Claude Etienne Minié. It came to prominence in the Crimean War (1853 to 1856) but Minié-derived weapons became the most common firearm in the American Civil War due to their accuracy.
The bore of this new rifle had grooves (“rifling”) in it which slowly twisted as they went from the back to the front of the weapon. The back of the bullet had a conical base with three rings which expanded when the gun powder was ignited. The base then filled into the barrel’s rifling which gave the projectile a spin, thus making it much more accurate. The adoption of this ammunition allowed soldiers to reload their rifled muskets faster and fire them more accurately. This increased the lethality of weapons used on the battlefield and effectively rendered conventional line infantry tactics obsolete.
This artifact was legally recovered by friends metal detecting in Civil War activity areas that include Gettysburg, PA; Mumma Farm, Antietam, MD; Kennesaw Mountain, GA and Appomattox, MD.
The bloodiest single-day Civil War battle took place on September 17, 1862, at Antietam, MD (according to historian and author James M. McPherson, 22,717 dead, wounded, or missing). The battle ground included Mumma Farm, its structures being burned by Confederate soldiers to prevent Union soldiers from utilizing them as sharpshooter positions. It was the only civilian structure destroyed during the battle. The Union’s tactical victory allowed President Lincoln to issue the Emancipation Proclamation on September 22.