I don't have a discovery, but this may be of interest to you. I have shot the crows, preds, cphps and eujins both 28 round nose and 31 gr pointed from my falcon hunter. I have also done some very basic 30 yrds comparisons to see impact differences. I wasn't shooting at a fantastic target (a piece of barn board), but as ridiculous as it may sound I think it is comparable to shooting small game... sort of tougher exterior and softer interior. Anyway's from this distance they all penetrated at least 3/4" without going all the way through, the wound tracks and impact noise were where the differences became more obvious to me. Cphp: make a small hole, narrow channel, pellet nearly flattens and not much noise. Crows: larger round hole and a channel that does get some what wider as it goes, pellet does not expand all that much, and its shape is not overly distorted, these pellets really need to strike something really hard while moving fast in order to expand however, shooting from the close distances which would be needed to keep the fps up you are more likely to have through and through shots as apposed to good expansion. So I am not really sure what the proper place to use them is? Predators: thin hole, channel gets much wider the deeper it goes and the pellet doesn't expand uniformly, it sort of flattens and becomes thinner and taller, which explains the narrow yet wide wound channel, satisfying thud on impact. Eujins: large hole, large channel, loud thud, pellets do not change shape aside from a little flattening at the tip, did penetrate the deepest. I found my gun shots the pointed 31's much more accurately then the rounded 28's especially on windy days. Obviously the lighter the pellet the more the wind can impact it over distance. I didn't do the impact comparison with kodiaks 21gr at the same time, but i have shot enough of them to know they make a loud thud, a large hole and deep penetration. I read a while back that people use thin thin blades to slice an "x" into crows and that really makes them expand on impact, probably reduces over penetration as well, however, they are not the most accurate pellets for head shots on the best of days especially over 25-30 yrds so take your chances. That said I don't see why you couldn't make a thin slice into the heads of kodiaks which i find to be more accurate then crows and get a little expansion out of them? I just might try that :> Take it for what it's worth, hope it helps. Cheers