Yellowknife
WKR
Ft-lbs energy is not a wounding mechanism and will tell you nothing about what a bullet will do in tissue. There is no bullet that needs "1,800 ft-lbs energy to open", but every bullet has a minimum impact velocity for reliable upset.
Velocity of mass IS energy. It's called kinetic energy. 1/2mv^2 if I recall correctly. We are talking about the same thing by different names.
A 180gr 30cal solid at 3,000fps and a 180gr 30cal frangible at 3,000fps have exactly the same "energy". So how does knowing the energy help you in any way to understand what either bullet will do in an animal?
The have the same energy. No question about that. But that energy is used in different ways. With the expanding bullet is it used to "upset" the projectile and cause tearing and rending of tissue. With the solid it would used for straight line penetration. Obviously and clearly the bullet type matters more than almost anything other than placement. But for any given specific bullet type, energy matters also. There is no question that for any given bullet and muzzle velocity you will get more potential wounding damage at 100 yds than you would at 600. And that is directly due to the reduction in velocity, which again IS kinetic energy.
Again... not saying that the .257 and a 45.70 loaded to the same energy level will act the same on game. Nor have I ever put any stock in "minimum energy level" for a particular animal. But to say minimum velocity matters but energy doesn't is kind of arguing against yourself.