0-30 yards is doable, 0-40 is somewhat tough. Having a bow shoot dead on from 0-40 is a feat that I've yet to find. No matter what I did I had to raise the pin slightly off my point of impact, even at 30 yards. To me, in a hunting situation, there's too much room for error to try this. I think that in order to accomplish this you'll have to really lighten up on your arrow, maybe to the point of pushing the safety factor.
Just for reference I have my Hoyt RazorTEC shooting at 70# at a 29 inch draw. My arrows are GoldTip XT's that are roughly 28 inches, with 100 grain field tips. I can crank 309 f.p.s. through a chronograph and if I were to set my pin dead on at 25 yards I can go 0-30 with no problems, for 40 yards I'd have to hold a smidge high. It gave me too many problems and I just went back to a multiple pin sight, simpler and less thinking involved.