What is this thing? The Calico Light Weapon System guns have been on the market for about 30 years. They were a product of the early 1980s, and embraced polymer early on. Calico developed the Helical Feed System that stacks up rounds in a spring loaded spiral magazine. The Calicos are rifles and pistols that strive to redefine how assault weapons work. The novelty, is that the tubular magazines hold either 50 or 100 rounds. They weapons are available in .22LR, 9mm and .40 S.