You are absolutely right bigcountry. There is no "equation" that will give you the definative "knock down" power. Both are just useful tools for comparison. Again it comes down to the fact that big, slow moving bullets kill in a different way than small fast bullets. You will get no argument from me that the small,fast bullet may be the best tool for putting game down. It certainly is superior to a broadhead. But an elk shot with my setup will be just as dead, no question about that. Maybe he will run a few more yards, but I am having to be a better hunter to get close enough to game to shoot with a muzzy and I may have to be a better tracker to find him, just as I would with a bow and arrow.

If I want 30-06 results and ranges, I hunt seasons that allow me to use a 30-06. These are my limitations put on me by myself, you do what you want.

By the way, I measured my 20 and 12 gauge and the internal diameter of the 20 was .625 and the 12 was almost .75. Really big bores!