Anecdotes are not data, I know, but FWIW the only real-world shooting I’m familiar with that used a 12GA Foster slug, the slug penetrated a truck door, went through the driver’s arm, most of his torso, exited the driver, and embedded itself in the passenger. The shotgun had at most a 10” bbl, the slugs were those 1oz 1600fps Remingtons that Wal Mart carried forever, and the distance from shooter to target was slightly more than 40 yards.
@
jlw
If one wanted a lever action for… Americana reasons, I guess, would a .30-30 Marlin 336 be your recommendation?