Field artillery in the American Civil War

Field artillery in the American Civil War refers to the artillery weapons, equipment, and practices used by the Artillery branch to support the infantry and cavalry forces in the field. It does not include siege artillery, use of artillery in fixed fortifications, or coastal or naval artillery. Nor does it include smaller, specialized artillery classified as small arms.

The principal guns widely used in the field are listed in the following table.

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

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. Further classifications of the weapons were made based on the type of metal used, typically bronze or iron (cast or wrought), although some examples of steel were produced. Additionally, the artillery was often identified by the year of design in the Ordnance department references.

The smoothbore artillery was also categorized by the bore dimensions, 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 (117 mm) 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. But the rapid expansions of both combatant 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.

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