For just about any AR carbine, you will end up shooting mostly 55gr FMJBT for practice and plinking. Look around stores and online for lowest prices, and buy in bulk. An easy option is Federal that you can buy at Wal-Mart for $40 per 100. Gander occasionally runs a sale $30 for 100. Buy a case online to save even more.
What type of hunting do you want to do? Varmints? I have had good luck with the 50gr V-Max. Hunting larger game is somewhat frowned upon with 223/5.56, but most will recommend a bullet in the 60 gr range where it is legal.
