Bear heads without the bleeder blades are very sleek and penetrate very easy. I have seen them with the point unaltered blow through two ribs of a buck and not bend the head or the point tip. Of course, that was with a 38 pound bow and a 420 grain cedar arrow, maybe with a very heavy arrow and much heavier bow there could be different results. Years ago the guys around here were rounding them like a spoon, they claimed the proof was in the pudding. I think perhaps, just 1/16" would be sufficient in case a harder bone than a rib was hit.