.357 Magnum, 110 grain JHP, OK defense round?

[Snyper]

The angle in which the arm is pointed makes it so you have to penetrate about 6" of the BGs arm before even entering the torso at all.

That's been repeated several times in the thread, but reality is an arm isn't as wide as a chest, and can't possibly cover it all.

Most "extended" arms are closer to shoulder level, leaving a lot of the torso exposed below

Also, most of the vital area of the torso is comprosed of lung tissue, so the comment about "filled with air" is pretty accurate.