Volley gun
Two notable artillery-sized volley guns were developed in the mid-19th century, although neither was particularly successful in practice. Developed in the 1860s and based on an 1850s design by a captain Fafschamps, the French mitrailleuse is an example of a multi-barreled volley gun that could fire all of its barrels simultaneously or sequentially over a short period of time. Also developed in the 1860s, General Origen Vandenburgh of the New York State Militia designed a weapon that had eighty five parallel .50 caliber rifle barrels. After failing to sell the weapon to the United Kingdom, he reportedly sold a small number to the Confederate States of America, although there is no record that they were actually used. One Vandenburgh gun was located at Fort Fisher, North Carolina, and another reportedly at Salisbury, NC.
Shotgun
A shotgun was originally a smoothbore firearm, which means that the inside of the barrel is not rifled but later rifled shotgun barrels and slugs become available. Preceding smoothbore firearms, such as the musket, were widely used by armies in the 18th century. The direct ancestor to the shotgun, the blunderbuss, was also used in a similar variety of roles from self-defense to riot control. It was often used by cavalry troops because of its generally shorter length and ease of use, as well as by coachmen for its substantial power. In the 19th century, however, these weapons were largely replaced on the battlefield with breechloading rifled firearms, which were more accurate over longer ranges. The military value of shotguns was rediscovered in the First World War, when American forces used 12-gauge pump action shotguns in close-quarters trench fighting to great effect. Since then, it has been used in a variety of roles in civilian, law enforcement, and military applications.