Get real, all this talk about different calibers and knockdown and blah, blah is some kind of armchair fantasy. Try this, you are standing in your front door and two dudes who have shown up at midnight asking for some unknown person pulls a large 38 and shoots you three times so that you are pronounced DOA. What caliber would have stopped the momentum of his actions even if you did have time to aim. only one, a sawed off shotgun. My wife and I now have 4 sawed off shot guns one in each car and two in the house. If anyone ever pulls a gun on me again we are at worse going to go to hell together. I have owned and operated over 400 guns they are all gone to other gun nuts except for a 100 year old lugar a glock 27 and a old ww 2 mauser, two of which hang on the wall. If 4 rounds of number 4 buck and one 000 buck won't do the job nothing will. I could be wrong but I doubt it.