I was shooting a piece foam 16 inches round and 24 inches long. It is for getting water out of pipelines, I thought it would simulate an elk body. I was amazed that a grizzly single bevel broadhead, hunting sharp, would cut an exit hole about 2 inches across with a plug of foam coming out that had a tail and looked like a tornado. Double bevel Zwickies only cut a slit on exit. Makes me realise how devastating the single bevel could be when spinning in the correct direction.