I have used thunderhead, muzzy, and wasp fixed blade broadheads since day 1. I will not use a mechanical broadhead because there is too much to go wrong. Anyway, I shot the Muzzy 4 blades and had a problem similar to yours. I switched to 3 blades and I' m not sure I will swith again. I recommend sticking to the three listed above. I have never had any problems with any of them. In fact I have a hunting buddy that has shot a thunderhead three blade into a brick and had it break the brick. Of course the broadhead got torn up but I still thought it was pretty impressive for a 100 grain broadhead to break through a brick.