An air gun is a gun design that uses compressed air or gas, typically carbon dioxide, to propel a projectile.

In the United States, air gun projectiles are typically .17 to .22 caliber although larger calibers are available. They typically shoot either BBs or shaped lead pellets.

Air guns do not use spring force to propel a projectile. Guns that use spring force are commonly referred to as BB guns.

aka:

• air rifles
• air pistols
• pellet guns
• pellet rifles

Footnotes / Sources:

“Glossary ⇒.” Sporting Arms and Ammunition Manufacturers’ Institute. Ed. SAAMI’s Technical Committee. Web. 15-18 Jan. 2011.