The American Civil War was one of the deadliest wars in U.S. history. The Battle of Gettysburg alone, for example, resulted in approximately 50,000 casualties. This high rate of injury and death was a product of technological advances in weaponry. New types of weapons -- such as modern bullets, machine guns and grenades -- made the Civil War as deadly as it was.

Minié Ball

One of the deadliest weapons introduced in the Civil War was a new type of bullet. The Minié ball, unlike previous bullets, was small enough that it could be quickly loaded into a rifle barrel by simply dropping the ball into the barrel. The ball did not require a long shaft to shove bullets into the barrel like previous bullets required. In addition, the bullets were conical shaped and highly accurate. Though a small invention, the Minié ball alone is believed to have accounted for 90 percent of all Civil War casualties.

Gatling Machine Gun

One of the earliest machine guns, known as the Gatling Gun, was also introduced during the Civil War. The gun had six barrels and could fire as many as 350 rounds in a minute. The Gatling was never purchased by the U.S. government, but Union General Benjamin Butler privately purchased several that were used in the 1863 Petersburg Campaign. The Confederate Army had a similar model, known as the Williams Gun. Both machine guns were heavy and inefficient, and were mainly used for defending strategic infrastructure.

Repeating Rifles

Rifling advanced significantly during the Civil War, and the repeating rifle was a new weapon used in battles. These hand-held rifles were similar to machine guns in that they could shoot multiple rounds without needing to reload. Popular models included the 7-shot Spencer Carbine and the 16-shot Henry rifles. The Spencer Carbine could unleash its seven shots in 30 seconds. The vast majority of these deadly weapons were used by the Union, as the Confederacy did not have the know-how needed to build them.

Grenades and Mines

Hand grenades and both land and water mines made an entrance in the Civil War. The Union's Ketchum grenade was widely used, though not always effectively. At the siege of Port Hudson, Louisiana, for example, Confederate soldiers caught the Ketchum grenades with blankets and tossed them back at the Union soldiers. The Confederacy, meanwhile, made advances in mining technology. Because the South was fighting a defensive war, it often buried iron containers filled with gunpowder and a fuse underground. During Sherman's March to the Sea, numerous Union soldiers were killed by buried landmines. The Confederacy's underwater torpedoes also succeeded in sinking multiple Union ironclad ships.