An earlier thread focused on " minimum impact energy" for a clean kill.
How about a Taylor Index Recommendation of:

17-20 for black bear and deer
20-40 for elk and grizzlies

See which calibers make the cut using the Taylor Index:

http://www.loadammo.com/Topics/July02.htm (Push thru to charts at bottom!)

North American hunters appear to be pretty well fixated on kinetic energy; however, here is a different viewpoint that encapsulates two of the three components of " killing power" put forth by P.O. Ackley (Kinetic Energy, Momentum, Shock). All we need now is a computation for hydrostatic " shock" to work into the mix.

Any thoughts?
[Boo, Hiss, Big Bore Drivel, Nonsense, Where' s Africa?]
Helps to explain why the Marlin Guide Gun in 45-70 or 450 Marlin is a favorite in Alaska (the " Africa of North America" )

Never Go Undergunned,
EKM