The Calico M100 is an American semi-automatic carbine.
The weapon was produced and designed in the 1980s.
The M100 is a carbine that operates using the blowback principle. It has a unique high-capacity helical magazine mounted on top of the weapon, which it feeds from. The weapon ejects from the bottom, making it suitable for ambidextrous use. However, the sale of the weapons to civilians was made illegal following the introduction of the Federal Weapons ban; the ban has since been lifted and Calico can now produce the weapon in its original configuration.
A version of the weapon with a walnut stock.