Mark,
While the height and shape of the comb, plus the height of the scope, have a lot to do with it, a rarely discussed stock dimension can cause the same "bite." Pitch is essentially the angle of the end of the butt, and the wrong pitch can also cause the comb to rise into your face, due to the bottom of the buttplate or buttpad putting more pressure on your shoulder than the top of the plate/pad.
A length of pull that's too long or too short can also result in cheek bite.
