So, I just took an ewe at 275 yds with Hornady Interlock shot out of a 338 Win Man. I expected that she would just roll over and die after being hit that hard, but much to my chagrin that was not the case. Shot number two took care of the problem.
However, the Interlock did very little internal damage to the animal. THe shot entered her ribcage 3 ribs from the rear. It broke 3 ribs, and angled up and towards her stomach, taking out a lung, her diaphram, a stomach (I presume, as there was some grass around), and exited her belly. When I shot her the second time, I could see the exit wound from the first shot. It was a pinhole!
This all brings up an interesting point. I probably would have been just as well off to shoot that ewe with a .223, as very little energy was transfered to her body, judging by the wound.
I wonder if we were to begin considering the bullet velocity after exiting the target if this whole issue of "knockdown power" would go away. There are two ways of looking at this problem. THe first is via the energy loss of the bullet. The second is via energy gain of the target. WHat if the target has some inherit capacity to absorb energy, no matter how hard you hit it?
Let's consider ballistic gelatin. Let's say we have a 12" by 12" by 12" block of ballistic gelatin. A 45 Colt and a 454 Casull are loaded such that the projectile is identical, but that the 454 has significantly greater muzzle velocity. After the shots are fired, it is found that the channel made in the gelatin from each shot is identical.
Which block was hit harder? I would guess that that the amount of energy transfered to the gelatin by each shot was nearly identical. I would also expect that the projectile shot from the Casull exited the gel a a higher velocity. All that extra knockdown for nothing!
If you are shooting clean through your animals time and again, you are probably shooting more gun that you really need.
This is the work-energy theorem, and I have never seen it cited when discussing the relative knockdown power of different calibers. I find that odd, as nearly everone with a degree in math, the physical sciences, or engineering has been exposed to it.
Maybe the conversation should shift to the inherit capacity of a game animal to be knock down. Being relatively frail and thin, the bullet had less opportinity to transfer energy to this sheep, as opposed to a heavier animal such as a moose or a big bear. I wonder if game animals have some inheritly asymptotic capacity to absorb energy from a bullet wound, regardless of how much KE the bullet carries when it strikes the animal?