The M100 is a blowback-operated

semi-automatic rifle A semi-automatic rifle is an autoloading rifle that fires a single cartridge with each pull of the trigger, and uses part of the fired cartridge's energy to eject the case and load another cartridge into the chamber. For comparison, a bolt-act ...

chambered in

.22 LR The .22 Long Rifle or simply .22 LR or 22 (metric designation: 5.6×15mmR) is a long-established variety of .22 caliber rimfire ammunition originating from the United States. It is used in a wide range of rifles, pistols, revolvers, smooth ...

, manufactured by Calico Light Weapons Systems in

Elgin, Oregon Elgin is a city in Union County, Oregon, Union County, Oregon, United States. The population was 1,711 at the 2010 United States Census, 2010 census. The community is named after the ''PS Lady Elgin, Lady Elgin'', a ship lost on Lake Michigan. Th ...

, United States. It was originally designed and released in the 1980s to be of use to law enforcement and military markets due to its slim profile.

Legislation

Possessing a unique 100-round helical-fed magazine mounted on top of the weapon, the introduction of the

Federal assault weapons ban The Public Safety and Recreational Firearms Use Protection Act, popularly known as the Federal Assault Weapons Ban (AWB), was a subsection of the Violent Crime Control and Law Enforcement Act of 1994, a United States federal law which include ...

made manufacture of the Calico family of weapons for sale to civilians illegal, until the legislation expired on September 13, 2004, in accordance with its sunset provision. The company is now allowed to build the exotic firearms in their original configuration.

References

{{Use dmy dates, date=June 2017 .22 LR semi-automatic rifles