Over penetration is an issue depending on round. Hell: a 9mm hard ball can over penetration. It's why hollow points exist. 22lr when shot at a wet target end up in said target. 5.7, in default bullet config, goes through and through by design. Do they make soft point hollow points, yes, but the default ammo was designed for speed and 3a body armor penetration. Again, over penetration IS a concern in some applications, and your ignoring that. I never said that it was THE issue. But I'm general, there are rounds that can do the exact same thing (kill or incapacitated) without the risk of the bullet making a through and through shot. Even in 5.56, it's bullets are designed to tumble in the target for maximum damage. If pass though was so great, hollow points soft points etc wouldn't exist.