Wow! I am glad you all sorted that out amicably. I was busy or would have been in the middle of it. As it is, by being silent, I learned something.
But I, like Archangel, own a .45 ACP and am a fan of the 850 fps bumble bee round. It does amazing damage! Part of the reason for that is momentum transfer, and momentum is calculated as mass * velocity. By contrast, bullet energy is calculated as 1/2 * mass * velocity^2 , where the "^2" symbol means to take the mathematical square of the velocity. So energy goes up dramatically as you increase bullet velocity.
But momentum
transfer is not just mass * velocity. There is also a coupling factor, which ranges from 0 to 1.0 and which sort of measures how much of the momentum actually gets transferred to the target. Big bullet diameter is a fool-proof way to push this factor closer to 1.0. Some also argue that slower bullet speed actually increases the coupling factor, because it gives more time to involve more tissue and spread the impact to a wider area of the target, as the bullet interacts with the target. Some would even say that the increase of coupling factor as bullet speed decreases is faster than the decrease in momentum as bullet speed decreases. Therefore, decreasing bullet speed can result in
more momentum transferred to the target. All of these effects, of course, would be most observable in only certain ranges of bullet speed, for certain shapes of bullet, for certain characteristics of the target (tough bear hide versus thin deer skin) and other factors.
I say that the amount of momentum transfer is directly related to what has been called "knock-down power". Momentum transfer is also somehow important to bullet impact "shock".
So basically I am agreeing with Archangel. Slow, fat and heavy can be really, really good. (Except for bullet drop, etc., as has been pointed out...)
But I also like a 2000 fps 250-300 grain .45" bullet. In a Katrina-like emergency, you never know when you might need to shoot through 1/4"-thick tempered glass, disable a vehicle's mechanics or batter down a door/gate lock or hinge, etc. This is really hypothetical, but you won't detract from your animal-target lethality enough to matter, just because your 300 grain .45" dia bullet is moving faster than 1500 fps rather than slower than 1000 fps. I don't want to stand a take either bullet
.