I think we need to understand one thing here, handguns are NOT POWERFUL. They do not really give you wound channels because of high velocity or bullet weight. They punch holes in people, that is all they really do for the most part. They have neither the velocity or bullet weight to do anything other then that. Yes, sometimes they seem to do miraculously things, but that is the exception rather then the norm.
The best way to stop someone with a handgun is to stop the messages to the muscles, and the best way to do that is break the spine or kill the brain. So your 7.62 x 25mm would have the penetration to do that.
Ok, I will go back on my meds now...