Abstract: Apparatus and method of providing for a semi-automatic crossbow embodying a new cocking device and a new magazine. The cocking device consists of a pulley system mounted to the frame of the crossbow and operated by a filament. The crossbow is cocked by holding the grip of the device in one hand, and pulling the cocking handle with the other hand. Each time the crossbow is cocked, a pulley carriage is automatically returned to its original position by use of springs or elastic bands. The device may be fired as quickly as the device may be cocked and trigger pulled. A clip device is utilized to hold bolts to be fired. The bolts are stacked vertically and spring fed upwardly to the chamber each time the crossbow is cocked. The bolts are held in place by constant spring pressure against the bolt track along which the bolt are driven. The clip utilizes two arms that scissor upward and raise the bolts substantially levelly.