I'll be honest with you. I've got no idea. There are so many different results from different tests its hard to sort out the hype. A pure gelatine test, if done with all the different bullets shows how each bullet expands in a "perfect" scenario such as shooting an assailant who was naked and didn't have any bones.
I know that the testing is done for comparison only but I'm not sure how valid any of the results are in the real world. It's been said that the 125 grain 38 caliber bullet has the most "one shot" stops. I believe that is from a .357 magnum. If I ever and I pray I don't, have to shoot someone I don't plan at stopping at one hit I will shoot till the gun goes click so "one shot" stops don't account for much in my opinion.
I think that it is so much more important to hit a vital area with a bullet than depend on any bullet to expand. There are just too many variables ie. speed of bullet,clothing,bone ,obstructions etc. to consider that any bullet will expand every time. A caliber sized hole in a vital area will let the air out an assailant and stop the threat. This is all just my opinion. You should do your research and reach your own.
Len