I hunt in weedowee ala and I use my hunting land to get out to (800) I can go further but just for practice. you might want to find a farm and do a few add and ins for the use of a field or 2. We are going out shooting this saturday so might be short notice but maybe we can set up another saturday and you can join us or something. send me a pm if your interested.
Maple Ridge Gun Club in Cullman Alabama has a rifle range to 500 yards, pistol and sporting clays. Golf carts for your use. Open on weekends and will open during the week if you call ahead. Nice people.
I am sure Ft Benning, Ga has a 1K range for the sniper school. It is probably available for civilian use on some weekends. There is a law that the military has to allow civilian access to the rifle ranges. Just tell'em I said you could shoot and I'm sure they will salute and say "All The Way".
There's a monthly match down at Auburn that shoots out to 1000. I'm planning attending this year. As I understand, you can come with a good one hundred yard zero on the Friday before the match and get some spotting/coaching help.