I can blow a hole through a 3/4 inch piece of plywood at 30 yards with my gun/choke/X-tended 6s, with almost 150 pellets in an 8x10 target at 45 yards (30+ in vitals). I won't even hesitate to take a clear 50 yard shot on a bird standingin a pasture...

With that said, even with 15/20 vision IMO there's too much "stuff" in the woods for a safe shot over 40 yards, with 25 to 30 yards the optimal distance. It only takes a single 1/4" sapling to completely ruin your gun's pattern and to me, the only feeling worse than shooting and missing, is staying home in bed