Quote Originally Posted by Jack Judah View Post
It depends on the rifle, the ammo, what Persons A and B are wearing, what angle the entry wound is on Person A, etc., but it's definitely possible. Sounds like there's a steep angle involved, which makes it more plausible. What damage Person B takes really is going to come down to the ammo and luck.
Thanks Jack! Yes it always comes down to ammo and luck doesn't it? Good note about the clothing too.

From what I could find online it appears the speed and energy of period rounds like the Winchester .44-40 are very roughly equivalent to modern handgun bullets of similar caliber.