Personally, I think armoredman gave you some spot on advice, . . . which goes back to training.
If you want to use it in your defense, . . . train to use it, . . . try it and see how you maneuver with it through doors, around obstacles, . . .
Then try to do it in pitch blackness. You know your house, . . . furniture, . . . pitfalls, . . . etc. and the boogey man will be at the disadvantage.
As far as not using a full rifle caliber round in a house, . . . all I can ask is "Why the devil not????"
If I decide to pick up my personal battle rifle in .308, . . . the bad guy better just hope he can outrun 2600 ft per second lead. I can patch walls, replace windows, . . . maybe even replace a TV or a fridge if needed, . . . but I doubt if Walmart has any spare parts for the boogey man. And there is only one place in the whole house that my rifle won't penetrate, . . . and I know how to defeat that too.
Main battle rifles didn't earn their name because they were tacticool, . . .
May God bless,
If you can breathe, . . . thank God!
If you can read, . . . thank a teacher!
If you are reading this in English, . . . thank a Veteran!