Are the tipsactually hitting the arrow nocks intarget causing the cracks, or is it from the arrows slapping the shafts together after hitting target in tight groups? I can't see thatdetail from 60 yards and my nocks are not broke, so I figured the shaftswere slapping each other, or the nock was hitting my rest/bow shelf. If the tips are truely hitting or brushing off ofthe nocks, then yes I need to get bushings.