I can't answer the question, but FWIW, for cup and core bullets the length of the wound channel is fairly constant over the range of impact speeds from 2100 to about 2750 FPS. Below that, the channel is actually longer because the bullet fails to open. Above that, the channel is shorter because the bullet begins to break up and shed more weight than is optimum. Premium bullets extend those limits. Partitions, for example, open at 1700-1800 FPS and hang together up to warp 9.5.
So for a given bullet, if speed does not lengthen the wound channel, it probably doesn't do all that much to increase killing power. And nobody seems to have a definitive formula for killing power, anyway.
But speed does get you more range, and that's often very important.
Now if you want to compare the 220 Swift to the 9.3x67, that's a more complicated discussion.
DISCLAIMER: As I've said on here many times, I'm not much of a hunter. My interest is in the technical side of the hobby.
Last edited by denton; 08/31/15.
