The Gatling Gun
The Gatling gun was not a true automatic weapon, though it was capable of maintaining a high rate of continuous fire while being cranked by its operator. It was viewed by the army hierarchy as a piece of artillery, and it resembled a small cannon in that it was mounted in a gun carriage when it was first deployed in combat, and it was about as heavy as a field cannon. The US Army did not officially deploy the Gatling gun during the Civil War. Several of the guns saw service when they were purchased privately by Union officers, a practice officially frowned on but tolerated by the War Department.
The US Department of the Navy was the first federal department to officially purchase the Gatling, installing eight of the weapons on river gunboats. The guns, purchased privately, were used by the Union Army in the trenches around Petersburg and Richmond at the end of the Overland Campaign in 1864. They then advanced with the Union army as it moved to cut off Lee’s retreat at Appomattox in Virginia. The army was impressed with the performance of the weapon and in 1866 authorized its purchase for use on the western plains. The Seventh Cavalry and other units were equipped with Gatling guns, though cavalry commanders such as Custer and Sheridan disdained using them as they slowed movement.
Custer’s failure to take Gatling guns with him to the Little Big Horn is often cited as contributing to his decisive defeat and death, but it is unlikely that they would have made much difference as far as his part of the attack. Gatling’s of the day were mounted similarly to artillery, and the rate of fire created a large cloud of smoke, impeding the vision of the operators, who were in an exposed position. In an assault, which was Custer’s plan of attack at the Little Big Horn, the guns would have been out of range, though they could have supported a defensive posture.
The Gatling was used to support the charge up Kettle Hill at the Battle of San Juan during the Spanish-American War. A little known fact of the battle is that three Gatling guns mounted on swivels were used to sweep the Spanish positions on the ridge, both suppressing return fire and knocking out several defensive positions. The Gatling guns managed a rate of fire on the hilltop of 700 rounds per minute per gun for over eight minutes while the Rough Riders climbed the hill, on foot despite their famous moniker. Despite this achievement, the Gatling gun was already in the process of being replaced as an infantry weapon.
The Gatling used multiple rotating barrels operated by a crank mechanism, which fell out of favor when the development of gas operated automatic weapons led to their introduction to the battlefield. In 1911 the US Army designated all of its arsenal of Gatling guns to be obsolete and removed them from service. The principle of the design later regained favor as airborne and shipboard weapons and several versions are in use today, including systems designed as defenses against cruise missile and unmanned aerial vehicles.