my 2 cents: use whatever JHP you like. Apartment walls do very little to stop bullets, so the key is to not miss your bad guy. Quality JHP's wont have much zip on them if they exit the bad guy's body, so i wouldnt worry too much unless there's someone right behind them.
That said, my preferred round is Federal HST 147. If you want to cut down on penetration, go with the 124gr stuff.
That said, my preferred round is Federal HST 147. If you want to cut down on penetration, go with the 124gr stuff.