I would only use frangible ammo in an AR for home defense. Something like Hornady's V-MAX 55gr varmint rounds (which are sold under the TAP Urban brand for LE use). There's just too much risk of overpen and taking out your neighbors dog or something. I know ARs are very popular for home defense but just not something I feel comfortable using when other options are available for that scenario.
I personally use an MP5 with 115g Speer Gold Dots for HD, but that's me.
EDIT:
@Cool Dog Check out Ivan the Troll's 3D printer files for receivers.