Number of rounds fired isn't a great metric.
Shot effectiveness per round has to factor in as well.
I've shot a lot of tough ass animals (coyotes and feral hogs mainly) with both AR's and shotguns inside 50Y.
They almost always run off from a solid AR hit to the chest and require a followup to dispatch them humanely, they almost always flop and die on the spot from #00 to the chest.