Crossbow bowstring positioning systems are provided. In one aspect of the invention a crossbow bowstring positioning system has a crank housing supporting an axle and positioning a first connector at a front facing surface of the crank housing, a length of rope connected between two separated points on the axle; a bowstring connector joined to the length of rope and connectable to a bowstring of the crossbow, a mounting having a buffer tube mount mountable to a buffer tube of a crossbow; and a crank operable to rotate the axle to control an extent to which the rope is wound onto the axle and a position of the bowstring connector relative to the axle. The crank housing and mounting can be readily assembled in a small space and an efficient manner while providing paths through which a force experienced by the axle during use can be resisted.