From all my reading of different posts, shotguns such as the 12 gauge Knight TK2000 or the White Tominator can be loaded in such a manner that makes then lethal out to 40 yards. Many modern shotguns can not compete with that. Top that shotgun with a low power scope or red dot and your one shot is all you need.

I hunt with a smoothbore .62 caliber (20 gauge) and loaded with 80 grains of Goex 3f and 100 grains of #6 shot I consider this a 30 yard turkey gun. I have not found a turkey yet willing to prove my theory but from the testing on the range and the pattern of the gun, I am more then sure the gun could do it.

I have no ballistic information but would not hesitate to hunt turkey or waterfowlwith one of the modern shotguns. Load it right and it will do the rest...