Wikipedia
Autococker
The Autococker is a closed-bolt semiautomatic paintball marker manufactured by Worr Game Products (WGP). It was one of the first paintball markers to be designed specifically for the sport, and has long been known throughout the paintball community for its popularity and customizability as well as its complexity. It is commonly believed that the closed-bolt design of the marker makes it inherently more accurate than its open-bolt counterparts, though this is disputed (see Accuracy, below).
Once a common sight at professional paintball tournaments (especially in the early- to mid-1990s), its popularity has since waned with the rise in popularity of electropneumatic markers.