Hey, use slugs, buckshot, a .308, .300 Magnum, hell, use a grenade if you will.
I'm concerned about family in the next room, neighbors, liability, etc., not "Internet tests".
My "evidence" comes from the field, not the internet...LOL! I have hunted and trapped my entire life and have seen what birdshot can do at close range (under 7 yards) out of a 12 Ga shotgun, so I'll stick with my birdshot.
Turn off your laptops this weekend, go out to a gravel pit, and SHOOT a load of birdshot at 4 or 5 yards (avg. living room distance might be closer to 3 yards), into a gallon jug filled with water. Test #6 birdshot out of a 12 Ga at close range. No, its not a slug or buckshot load, but it WILL leave a big, NASTY rat hole. You may just change your mind about what you read on the "net" from some Mall Ninja, or at least question as to if the person posting spends more time online than on the range.