Considering a bowhunt for bison...my dad is to be exact.

Thinking a 2 blade fixed would be most ideal for penetrating such a big animal. He currently uses NAP razorbak which is a 2 blade with 2 bleeders cut on contact. I believe the bleeders can be removed.

What would you recommend? 2 blade? 2 blade w/bleeders? fixed? expandable?