re: Anyone know when a “gunshot wound” wasn’t decidedly fatal?

A wound to an extremity almost invariably meant amputation. A shot to the torso was probably fatal but not always. They might probe the would for the bullet but there was nothing they could do to repair the damage.

One of my ancestors suffered an abdominal wound in a civil war battle and it never properly healed. He became a lifelong morphine addict as a result. It came from New Orleans by riverboat and family lore tells how he would have "screaming fits" if the boat was late.