The Winchester Liberator is a 16-gauge, four-barrelled shotgun, similar to a scaled up four-shot double actionderringer. It was an implementation of the Hillberg Insurgency Weapon design. Robert Hillberg, the designer, envisioned a weapon that was cheap to manufacture, easy to use, and provided a significant chance of being effective in the hands of someone who had never handled a firearm before. Pistols and submachine guns were eliminated from consideration due to the training required to use them effectively. The shotgun was chosen because it provided a very high volume of fire with a high hit probability. Both Winchester and Colt built prototypes, although the Colt eight-shot design came late in the Vietnam War and was adapted for the civilian law enforcement market. No known samples were ever produced for military use.