If you know how to work a gun in close quaters , splice your corners right , some body is in for a bad surprise, the rounds i use will not penetrate my house walls, and if they do they will lose their velocity before they get out of the house. I use .223, and not my 9mm beacouse, .223 one to me the mechanics are easier, two iam more accuarte, and three iam better able to fight with an ar then a glock,