Siege guns are used to attack fortified positions. They are large, heavy and take time to put into place and setup. They are typically what we would commonly refer to as cannons. However, cannons could refer to any of the 3 types of artillery pieces used during the Revolutionary War.
Guns were fired at a low trajectory and could be used at either short or long range. Guns were very effective at battering fortifications of construction. They were often used against the enemy's cannon because they could be aimed with some accuracy. Guns could fire balls, bombs, canister shot and grape shot. During the war cannon balls and grape shot were the most common forms of projectiles.
Garrison guns were mounted on a small 4-wheeled carriage. They were not meant to be easily moved about once set up in their firing position. Field guns were mounted to to larger carriages with 2 wheels. The entire piece could be hooked up to a caisson and moved about by horses, or moved by the firing crew for small distances.
When it was determined that guns could not penetrate an enemy's fortifications, then mortars and howitzers were then used to inflict damage. A mortar was used to fire a high-arching projectile that, if timed properly, would be exploded in the air over the enemy and behind their fortifications. The howitzer could fire an exploding shell and was directed toward the defensive works.
The heaviest guns used at Yorktown were in the 18 and 24 pound siege guns. A siege gun is one designed 18 pounds or higher.
Black powder was the common gun powder used during the war. It was made up of saltpeter, ground charcoal and sulphur.
Field guns had an effective range of about 1,000 yards, or just over 1/2 mile. They could under ideal firing conditions reach up to 2,000 yards.
The National Park Service has 11 pieces that were actually used during the 1781 battle at Yorktown. Nine of them are pieces mounted at the Surrender Field pavilion. The other 2 are on display inside the visitor center. The rest of the cannons on display in the field are authentic looking 20th Century replicas.
PROJECTILES are what comes out of the barrel of the cannon. The artillery pieces are sized according to the weight of the projectile being fired. For example an 18 pound cannon would fire an 18 pound cannonball.
BOMBS projectiles fired from a cannon that explode after a predetermined time
SOLID SHOT projectiles that did not explode and were usually a solid piece of iron. This type of projectile could also include bar shot (2 halves of a cannon ball connected with a piece of chain), and chain shot (2 solid balls connected with a short chain).Round shot was more efficient.
SCATTER SHOTE small fragments of metal that could be small, marble sized pellets, even nails that could be fired. Also called grape shot and canister shot.