The Agar “Coffee Mill” gun suffered from the same fate as a many a middle child: Perhaps a little less athletic, a little less good-looking than its elder sibling, the Gatling gun, its achievements were quickly overshadowed and forgotten despite its attributes.
Where you’ve seen it:
Though I’ve never played it, the first-person shooter History Channel Civil War: Secret Missions allows the player to man one of these rapid-fire stationary guns. And it’s from the History Channel, so it must be educational, right?
A depressing truism about mankind is that it does its best thinking during times of war. During the American Civil War, both sides recognized the need for rapid-firing anti-personnel guns—weapons lighter and faster firing than a cannon, but providing an overwhelming advantage in firepower against musket-armed line troops. To that end, Wilson Agar marketed his single-barreled, carriage-mounted design to the Union army as an “army in six feet square.” In 1861, Abraham Lincoln, who personally attended the weapon’s field trials, described the Agar gun as “worth the attention of the Government.” Ten of the guns were bought straightaway, and another 54 were ordered for manufacture. Despite this promising start, the Agar design was quickly condemned by the Union Army’s Ordnance Department for eating too much ammo and being prone to overheating and jamming. As a result, most of these guns were only sent to cover remote locations and never served a significant role in the war.
Fifty-eight caliber paper cartridges were loaded into re-usable metal tubes, and a percussion cap was fitted to a nipple at the rear of the tube before the round was dropped into a funnel-shaped hopper. The hopper looked like a coffee mill grinder, hence the moniker “Coffee Mill Gun.” Those steel cases were expensive to produce and easy to lose, which also contributed to the gun’s premature obsolescence.
Turning a hand crank on the rear of the gun (right) fed rounds from the hopper and fired them in the same motion. Each time a round dropped into the chamber, a wedged locking block would rise into place to secure it as a cam-operated hammer struck the percussion cap. The empty steel casings would drop into a pan beneath the gun after each shot, allowing the crew to grab them, reload them, and drop them back into the hopper before the gun ran out of ammo. Given the Agar’s relatively high rate of fire per the time period—120 rounds per minute—it took a sizable crew to keep up. This, combined with the gun’s single-barrel design, rendered it vulnerable to overheating. To combat this, Agar provided a pair of replacement barrels to be carried with each gun and swapped when the barrel got too hot. Agar also thought up a cooling system, where air from a turbine (powered by the same hand crank used to fire the weapon) was forced into a metal jacket that sheathed the barrel.
Despite its innocuous-sounding name, the “Coffee Mill” gun was clearly an impressive invention that, had everyone just listened to old honest Abe and let it see more use in the field, would have played a much more crucial role in turning the tide of the Civil War.
Primary image courtesy of amoskeagauction.com.