You are not giving a lot of informations. If you like the AR style, and price is a I would recommend getting a piston upper, or get a short DI upper and have it coated in nickle boron to make cleaning super easy. There a lot of options though and if you wanted to branch of of the Ar platform check out the Arsenal 106cr, cut down the barrel and you have a 5.56 AK SBR. Like I said there are a lot of options so have fun with it.