Most law, in a self defense situation is quite clear, you as a reasonable person, on seeing a threat that would cause you death, or grievous injury, can use as much force as reasonably necessary, and again "up to, and including causing death" to stop that threat.
A bad end to shooting to wound comes from Israel, a young Army Officer, on leave, is awakened by neighbor, "there is a man, crazed, stabbing people in the market" he goes outside with his pistol (a BHP) the young soldier calls on the man, to drop the knife, he does not, and is shot in the leg, then the other leg (thigh? hard ball 9mm) by this time the distance is a mere 3 feet, and the soldier is stabbed to death.
Shooting to stop a threat, one you, the armed for self defense person sees as real! Shots to center of mass, repeated till the threat is no longer there, that is a valid, and legal response.
And let us face it, why would you shoot someone if your life was not in danger? or the life of some one under your care and protection.