Blood I can clean up.
With a sawed-off shotgun you only need to re-plaster the walls a little and then paint over.
Knife.
Big and sharp.
Drywall is cheap.
The AR loaded with frangible ammunition might be a good choice. It’s designed to shatter on impact so as to minimize the possibility of over penetrating.
If a shotgun is your choice I’d recommend 7-1/2 birdshot for inside the house. At 20 feet it’s basically a column of lead pellets about 2 inches in diameter.
Best,
L
Lots of tests on the web....
Bottomline- 556 soft/jhp are awesome on tissue, but comparatively mild compared to pistol or shotgun slug and buck. Bird shot at close range is a slug for interior wall penetration concerns.
I like 40 grain Hornady varmint bullets, tipped or not, for my first 10 rounds in the mag, then 75 or 77 grain JHPs-
They all will defeat a Level 2A or even 3A soft armor, which is an added bonus in this day and age.
Fro a 16 inch carbine, you have an accurate go to weapon for zero- 200 m, plus the ability to add optics or other useful gizmos. Mine wear a 2 MOA dot 1x optic, and back up irons. Sometimes a flash light and vert front hand grip.