This exact same thing happened to friends of friends.
The guy was “fiddling” with his shotgun, and it “accidentally” fired, hitting the girlfriend center mass.
Of course, being true brainiacs, the rural cops immediately bought the story and the perp was not charged.
So, to paraphrase O.J. Simpson, “If you do it, here’s how you do it.”
Amazing.
It killed the girl in my story, too.