I use a Gold tip XT5575 tipped with a Rocket Hammerhead expandable 2in cutting dia. The idea behind springs,washers,hooks and other things is to expend all of the arrows energy into the bird without pass thru. The embedded shaft restricts movement to prevent running or flight. My idea is to use a large cutting dia. to do the same thing while giving me a little larger margin for error on a very small vital zone (top of drumsticks,wing base muscles or spine) and give massive tissue damage for a quick clean kill. Only one for me so far,last yr. Stuck him at 9yds,he went down at 24 never flew staggered. 350gr arrow,bow backed down from 70lb to approx 65. (Guessing 260-270fps) shoots 280 at 70lb. Good luck it's a tough game but if you ever get one w/bow it'll be hard to pick up a gun ,but it can be done on special occasions.