The musketoon is a shorter barrelled version of the musket

Musket

A musket is a muzzle-loaded, smooth bore long gun, fired from the shoulder. Muskets were designed for use by infantry. A soldier armed with a musket had the designation musketman or musketeer....

, and served in the roles of a shotgun

Shotgun

A shotgun is a firearm that is usually designed to be fired from the shoulder, which uses the energy of a fixed shell to fire a number of small spherical pellets called shot, or a solid projectile called a slug...

 or carbine

Carbine

A carbine , from French carabine, is a longarm similar to but shorter than a rifle or musket. Many carbines are shortened versions of full rifles, firing the same ammunition at a lower velocity due to a shorter barrel length....

. Musketoons could be of the same caliber

Caliber

In guns including firearms, caliber or calibre is the approximate internal diameter of the barrel in relation to the diameter of the projectile used in it....

 as the issue musket, or of a much larger caliber, 1.0-2.5 inches (25-63 mm). The musketoon is most commonly associated with naval

Navy

A navy is the branch of a nation's armed forces principally designated for naval and amphibious warfare; namely, lake- or ocean-borne combat operations and related functions...

 use, and pirates in particular, though they also served in a carbine role with cavalry

Cavalry

Cavalry or horsemen were soldiers or warriors who fought mounted on horseback. Cavalry were historically the third oldest and the most mobile of the combat arms...

. Musketoon barrels were often flared at the muzzle, resembling a cannon

Cannon

A cannon is any piece of artillery that uses gunpowder or other usually explosive-based propellents to launch a projectile. Cannon vary in caliber, range, mobility, rate of fire, angle of fire, and firepower; different forms of cannon combine and balance these attributes in varying degrees,...

 or blunderbuss

Blunderbuss

The blunderbuss is a muzzle-loading firearm with a short, large caliber barrel, which is flared at the muzzle and frequently throughout the entire bore, and used with shot and other projectiles of relevant quantity and/or caliber. The blunderbuss could be considered to be an early form of shotgun,...

.

Description

Musketoons had a brass

Brass

Brass is an alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties.In comparison, bronze is principally an alloy of copper and tin...

 or iron

Iron

Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

 barrel, and used a wheellock

Wheellock

A wheellock, wheel-lock or wheel lock, is a friction-wheel mechanism to cause a spark for firing a firearm. It was the next major development in firearms technology after the matchlock and the first self-igniting firearm. The mechanism is so-called because it uses a rotating steel wheel to provide...

 or flintlock

Flintlock

Flintlock is the general term for any firearm based on the flintlock mechanism. The term may also apply to the mechanism itself. Introduced at the beginning of the 17th century, the flintlock rapidly replaced earlier firearm-ignition technologies, such as the doglock, matchlock and wheellock...

 firing mechanism, like the typical musket of the period. They were fired from the shoulder like the musket, but the shorter length (barrels were as short as a foot (30 cm) long) made them easier to handle in restricted conditions, such as mounted cavalry and naval boarding parties.

Smaller bore musketoons matched the caliber of the muskets in service, and were generally used the same way, with single musket ball or a buck and ball

Buck and ball

Buck and ball was a common load for muzzle-loading muskets, and was very commonly used into the early days of the American Civil War. The load consisted of a .69 caliber round lead musket ball combined with three buckshot pellets.-Construction:...

 load, while large bore musketoons were loaded with multiple buckshot or pistol balls (generally smaller in diameter than musket balls) and used as shotguns. It is this type of loading that is most associated with naval use.