[aa1911]

it will penetrate but will have next to no energy afterwards. It loses significant energy even through a car window for example. but yeah, anything you launch at extreme close range will do the job but if a 20yd shot was needed for some reason, #4 is quite good. BB shot sizes would be OK if worried about over penetration.

But buckshot wins for me if I had to choose, I want to put the badguy down for good.

or do cut shells! hahaa, that would put the hurtlocker on someone, getting a 'slug' of birdshot that explodes on contact, ouch.