I hope to hunt with my AR this year. I have enjoyed quite a few conversations with the Dept. of Conservation gentleman who is charge of our county. He too hunts with a .223 and he recommended a 64 grain soft point bullet. I ended up buying a box of Federal Fusion 62 grain bullets to hunt with.
Some of us don't have the extra $ to buy another gun. I look at hunting deer as a way to put some meat in the freezer inexpensively. If I totally get into hunting, then I might look at getting another gun.
As always, be safe. Get a good sight picture and be aware of your surroundings and what is beyond your sight picture. Good luck.