Dave - I have seen some of this in the past. The old Bear Razor heads used to shoot real well in some bows without the razor inserts, but were known to sometimes create wound "slits" that closed up shortly afterwards. These Rage two blades, however, seem to have a reputation for causing tremendous blood loss. Not sure if its' the the little COC point that is perpendicular to the blades - but for whatever reason they seem to work.