Agar gun

• 1. Introduction

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  The Agar gun arrived on American battlefields looking, of all things, like a coffee grinder. Its hand crank and funnel-shaped ammunition hopper sat on top like the familiar kitchen appliance soldiers knew from home, earning it the nickname that would follow it through the Civil War: the Coffee Mill Gun. But behind that domestic appearance was a weapon capable of firing 120 rounds per minute, at a time when a trained infantryman might manage three shots. When President Abraham Lincoln watched a demonstration in 1861, he was so struck by the weapon that he wrote, "I saw this gun myself, and witnessed some experiments with it, and I really think it is worth the attention of the Government." Ten guns were purchased the same day. What happened next raises a harder question: why did a weapon so impressive to the President of the United States end up guarding bridges and remote passes, rarely heard from on the main battlefield?

• 2. Wilson Agar's Invention

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  Wilson Agar gave his name to a weapon that belonged to a crowded field. About seventy hand-cranked machine guns were developed for the Civil War, all responding to the same wartime hunger for better killing technology. Agar's design stood out enough to reach the White House. He marketed the gun with a striking line, calling it "an army in six feet square," a claim rooted in its rate of fire rather than in any modest assessment of its own importance. The demonstration at Washington Arsenal in 1861 was the turning point. Lincoln ordered all ten available weapons purchased at $1,300 each, a price described at the time as very high. Later that same year, General McClellan placed an order for fifty additional guns at a reduced cost of $735 each. General Butler acquired two at the original $1,300 price, and General Fremont paid even more, at $1,500 each. Agar's invention had drawn serious military investment before it had fired a shot in anger.

• 3. How the Gun Worked

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  The Agar gun fired .58 caliber cartridges. Standard paper cartridges were loaded into reusable metal tubes, and each tube received a separate percussion cap fitted to a nipple at its rear, effectively creating a centerfire cartridge. The loaded tubes were then dropped into the funnel-shaped hopper. Turning the hand crank at the rear of the weapon fed tubes down from the hopper one by one. A wedge-shaped block rose up to lock each round in place, a cam-operated hammer struck the percussion cap, and the round fired. The empty metal tubes fell into a pan beneath the gun, where crews immediately began reloading them to feed back into the hopper. That cycle, from hopper to firing to pan to reload, put the gun's rate of fire in direct competition with the speed of the men working it. The Agar was a single-barrel design, which set it apart from multi-barrel weapons like the Gatling gun. Its classification places it alongside revolver cannons in a multiple-chamber, single-barrel category, where the hopper configuration is, in fact, the only alternative to the revolver arrangement to have been used in practice.

• 4. Cooling and Overheating

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  A single barrel firing 120 rounds per minute generates heat fast. Agar addressed this directly rather than ignoring it. He fitted the barrel with a metal jacket through which air was forced to provide cooling, and the air came from a turbine driven by the same hand crank that fired the weapon. Every pull of the crank simultaneously chambered a round and pushed cooling air past the barrel. That air carried an unintended benefit: it blew away fragments of unburned paper from the cartridges that would otherwise accumulate near the barrel. For situations where the jacket cooling proved insufficient, two spare barrels were typically carried with each gun so crews could swap out an overheated barrel and continue firing. The rate of fire was deliberately capped at 120 rounds per minute, partly as a measure against overheating. Even so, in sustained use the single-barrel design proved prone to failure in the field, a problem that would follow the weapon throughout the war. The built-in steel shield was another design feature that had no equivalent on other machine guns of the period, giving the Agar a silhouette that resembled weapons not yet invented, since single-barrel machine guns with similar shields would become standard in the First World War.

• 5. Combat Record

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  In January 1862, the 28th Pennsylvania Volunteer Infantry used Agar guns in a skirmish near Harpers Ferry. On the 29th of March 1862, at Middleburg, Virginia, a captain named Bartlett recalled Union soldiers directing an Agar gun at attacking Confederate cavalry at a range of 800 yards. The Confederates suffered many casualties and withdrew. The same guns served during McClellan's Peninsula campaign later in 1862. The weapon also crossed to the other side of the war. In September 1862, Confederate forces captured seventeen Agar guns when they took Harpers Ferry, and made some use of them in 1864. But these engagements were exceptions. The Ordnance Department condemned the gun for consuming too much ammunition to be practical, and the weapon was pushed toward defensive and secondary roles, guarding bridges and narrow passes rather than deciding open engagements. Jamming was a persistent complaint. The special steel tubes holding the cartridges were heavy and expensive, and they were frequently lost in the field. Brass cartridges would have helped, but the material was not widely available during the gun's active years. Its range of roughly 800 yards matched the rifle-musket carried by ordinary infantry, and military planners wanted longer reach from a weapon this complex to operate.

• 6. Decline and Legacy

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  By the end of the war, the Agar gun's moment had passed. In 1865, the few surviving weapons were sold off at $500 each, less than half the original purchase price and only a third of what General Fremont had paid. The gun had never been deployed in numbers large enough to prove its potential or expose its limits on the main battlefield. Like most machine guns of the Civil War period, it spent the conflict in conditions that kept it from demonstrating what it could actually do at scale. The problem was not entirely one of design. The infrastructure around the gun, the supply of specialized tubes, the trained crews needed to keep up the reload cycle, the doctrinal willingness to commit such weapons to the front line, was not yet in place. Machine guns would become far more central to battlefield tactics in the decades that followed, though not the Agar's descendants specifically. What the Agar gun left behind was a category: the single-barrel, multiple-chamber rapid-fire weapon, the same classification shared by the revolver cannons still in operational use today.