Which type of gun is characterized by a groove in the barrel?

A rifle is characterized by a groove in the barrel, which is known as rifling. This rifling consists of helical grooves that are cut into the barrel’s interior, allowing the bullet to spin as it travels down the barrel and exit at high velocity. The spin stabilizes the bullet in flight, improving accuracy over longer distances.

This feature is fundamental to rifles, as they are primarily designed for precision shooting and long-range accuracy. In contrast, shotguns typically have smooth barrels without rifling, which allows for the firing of multiple pellets (shot) rather than a single bullet. Handguns and revolvers can also feature rifled barrels, but they are not specifically defined by this characteristic in the same way that rifles are. Thus, the defining feature of grooves in the barrel clearly identifies the rifle.