I don't care if anyone thinks an AR-15 is a good home self-defense gun or not. If the day or night ever came, I'd leave my shotgun and .45 Springfield XDM alone and go for my AR!! Period, end of discussion. Even a FMJ bullet from an AR stands little chance of going through two or three brick walls it would take to kill a neighbor accidentally. And in Viet Nam and wars since, those FMJ bullets kill with extreme lethality, since a high velocity/low energy bullet expends most of it's energy in the first target it hits. I would use my frangibles or soft-nose bullets any who. But even a FMJ bullet from a .223 ain't gonna kill your neighbor. Even a JHP from my .45 would go through an intruder and keep going a while.