...#6 shot in a 12ga. perfect for apartments. Noisy but won’t penetrate dry wall...
I’ll bet it will at most any distance in any room in an apartment.
Nothing scientific. I’ve just seen what it’s done up close range to critters such as nuisanc! woodchucks. It blows their heads clean off at short range.
From barrel end to invader. I’m not talking at shooting at a blank wall for no reason. The guy would be between you and any wall.