I have been looking for a good defense load for a 20 GA. I got my wife a Moss 500 Youth Model for here home defense. I found a #3 Buckshot load from Winchester (2 3/4 inch, 20 pellet, 1200 fps). I patterned it out of another 20 GA (sawed off to 18 inch no choke) and at 30 feet I got an irregular 12 inch pattern. That is 20 pellets at .250 dia., which weighs 23.4 gr per pellet at 1200 fps. That is total weight of 468 grs. I have not yet did any penetration tests, but according to some research I have done it it is effective on small deer at out to 25 yards. So I think it would be very effective on an aggressive human victimizer. At only 23 gr per pellet I do not believe it would have much residual energy after passing though a common interior wall.