Add Yahoo as a preferred source to see more of our stories on Google. The US Army fired a nuclear weapon from its atomic cannon for the first and last time 69 years ago. The cannon, initially named ...

Add Yahoo as a preferred source to see more of our stories on Google. Part of Operation Upshot-Knothole, was a 15-kiloton test fired from a 280-mm cannon on May 25, 1953 at the Nevada Proving Grounds.