Page "Firearm" Paragraph 44

A long gun is generally any small arm that is larger than a handgun and is designed to be held and fired with both hands, either from the hip or the shoulder.

Long guns typically have a barrel between 10 and 30 inches ( there are restrictions on minimum barrel length in many jurisdictions ; maximum barrel length is usually a matter of practicality ), that along with the receiver and trigger group is mounted into a wood, plastic, metal or composite stock, composed of one or more pieces that form a foregrip, rear grip, and optionally ( but typically ) a shoulder mount called the butt.

Early long arms, from the Renaissance up to the mid-1800s, were generally smoothbore firearms that fired one or more ball shot, called muskets.