If you can't use a .223 in your state due to regulations, the Grendel is a great option. The .223 with heavy bullets (77 grain TMK) is a killer, but the Grendel is close second in my book. I have killed a couple dandy Axis deer with my first one (Encore MGM barrel) and I like it so much I bought a Ruger American Predator in 6.5 Grendel, just cuz. Chopped the barrel to 18" and modified the magazines so that they hold 5 but only stick below the stock by 3/4". With a suppressor on it, it is great kids gun and I loan it out all the time when I go to hunts that I know kids will be at. Most of the time they show up and are being asked to use 308s, 7-08s, or similar with muzzle brakes or some such. I put that Grendel with a suppressor in their hands and they are all smiles and go on to kill stuff.
Great little round that punches well above it's weight class.