The concept began with the Casull Model 290 that used a flat pan magazine similar to designs widely used prior to World War II.
A semi-automatic only variant called the American SAR 180/275 is still produced on a custom basis by E&L Manufacturing of Riddle, Oregon.
The American-180 was purchased mostly by private parties prior to the Hughes Amendment in 1986, which banned the production of automatic weapons for the American civilian market.
[7][8] Despite the low power of the .22 Long Rifle round, testing demonstrated that automatic fire could penetrate even concrete and bulletproof vests from cumulative damage.
[citation needed] However, the target would have to remain still for some amount of time to allow the cumulative damage to amass in the same area to achieve this.