ARTILLERY WEAPONS

There were two general types of artillery weapons used during the Civil War: smoothbores and rifles. Smoothbores included howitzers and guns.

Smoothbores

Smoothbore artillery refers to weapons that are not rifled. At the time of the Civil War, metallurgy and other supporting technologies had just recently evolved to a point allowing the large scale production of rifled field artillery. As such, many smoothbore weapons were still in use and production even at the end of the war. Smoothbore field artillery of the day fit into two role-based categories: guns and howitzers

The smoothbore artillery was based on the rough weight of the solid shot projectile fired from the weapon. For instance a 12-pounder field gun fired a 12 pound solid shot projectile from its 4.62-inch diameter bore. It was practice, dating back to the 18th century, to mix gun and howitzers into batteries. Pre-war allocations called for 6-pounder field guns matched with 12-pounder howitzers, 9 and 12-pounder field guns matched with 24-pounder howitzers. However with the rapid expansions of armies, mass introduction of rifled artillery, and the versatility of the 12-pounder "Napoleon" class of weapons all contributed to a change in the mixed battery practices.

Guns

Smoothbore guns were designed to fire solid shot projectiles at high velocity, over low trajectories at targets in the open, although shot and canister were acceptable for use. The barrels of the guns were longer than corresponding howitzers, and called for higher powder charges to achieve the desired performance. Field guns were produced in 6-pounder, 9-pounder, and 12-pounder versions. Although some older iron weapons were pressed into service at the beginning of the war most of those used on the battlefields were of bronze construction. By 1863 the union had phased out all but a few 6 & 9 pound guns.

The major shortcoming of these heavy field guns was mobility, as they required eight-horse teams as opposed to the six-horse teams of the lighter guns. Small quantities of 12-pounder field guns were rifled early in the war, but these were more experimental weapons, and no field service is recorded.

By far the most popular of the smoothbore cannon was the 12-pounder Model of 1857, Light, commonly called "Napoleon". The Model 1857 was of lighter weight than the previous 12-pounder guns, and could be pulled by a six-horse draft, yet offered the heavier projectile payload of the larger bore. It is sometimes called, confusingly, a "gun-howitzer" (because it possessed characteristics of both gun and howitzer) and is discussed in more detail separately below.


Howitzers

Howitzers were short-barreled guns that were optimized for firing explosive shells in a high trajectory, but also for spherical case shot and canister, over a shorter range than the guns. While field use alluded to firing at targets consisting of enemy forces arrayed in the open, Howitzers were considered the weapon of choice if the opposing forces were concealed behind terrain features or fortifications. Howitzers used lower powder charges than guns of corresponding caliber. Field Howitzer calibers used in the Civil War were 12-pounder, 24-pounder, and 32-pounder.

Rifled guns

Rifling adds spiral grooves along the inside of the gun barrel for the purpose of spinning the shell or shot and enacting gyroscopic force that increases the accuracy of the gun by preventing the shell from rotating along axes other than the axis parallel to the gun barrel. Adding rifling to a gun tube made it more difficult and expensive to manufacture and increased the length of the tube, but it increased the range and accuracy of the piece. While most of the rifled guns in the Civil War were muzzle-loaded, a small number of breech-loaded guns were used.

3-inch ordnance rifle

The 3-inch ordnance rifle was the most widely used rifled gun during the war. The rifle had exceptional accuracy. During the Battle of Atlanta, a Confederate gunner was quoted: "The Yankee three-inch rifle was a dead shot at any distance under a mile. They could hit the end of a flour barrel more often than miss, unless the gunner got rattled."

Parrott rifles

The Parrott rifle was manufactured in different sizes, from 10-pounders up to 300-pounders. The 10 and 20 pound versions were used by the Union Army in the field. Until 1864, Union batteries used only the 10 pound model. On the Parrott, a large wrought iron reinforcing band was overlaid on the breech. Although accurate, the Parrott had a poor reputation for safety, and they were shunned by many artillerymen. The 20-pounder was the largest field gun used during the war.