The choices are few. If you want a cheaper option, the public range up by Watauga Lake is exactly 20 miles from the center of JC. I don't know what the address is or what to tell you to use for a google maps search, but I can tell you that it's located at 36.308024, -82.106983 (had to pull that from google maps lol)
It's unattended, only has three lanes (a 25, 50 and 100 yard), and is frequently full, but it's really cheap (drop something like $5 into a box and put a card under your windshield), and there's no caliber restriction.