And vice versa. With a fair amount of water buff experience under my own belt, I would observe the following. Every bull I've seen hit in the right place -- perfect loccation and shot angle -- has gone down with no problem, no matter what weight bow. Every one hit anywhere else has been a bit of a drama, again, no matter what weight bow. I hate to offer a firm number on bow weight because circumstances vary so much, but everyone needs a starting point. I would regard #70 tackle as minimum and if you can handle 10# more, do it. Beyond that, it's probably overkill. Of course, this assumes heavy arrows, perfect broadheads etc. Accuracy inevitably suffers somewhat as poundage increases -- that's why tournament target archers shoot light bows. How much loss of accuracy is acceptable? That's for you to decide. But if you can't shoot #70 with reasonable accuracy, you shouldn't be hunting buff, IMHO. Above all, don't fall into the trap of thinking that if you're shooting #85, the buff is going to die. The arrow HAS to be delivered perfectly. Cheers, Don