Great idea but you'll need property that almost no one would want, in a location where nearby development is unlikely and establish yourself as a "shooting range" for a year so you'd be somewhat protected by the 2014 state law.
Moving dirt is expensive.
I think the best way is to establish the range legally before the area is incorporated and developed. Get in good with the local PD, offer them range benefits, etc. As you know, a city cannot create a law that expressly outlaws a range; they must have a grandfather clause.
As for land, there's no such thing as unwanted land. A developer will buy the worst swamp land and turn it into a super mall. Personally, I'd like to find a nice farm with plenty land so no city can say anything about what occurs on the property. It could be used for more than just shooting. Event hosting (like weddings), campsites, off-roading, horseback riding if anyone has horses, movie set rental, renting to instructors, hosting courses for LE departments, etc. So many possibilities.