It's a long drive from Florida, but West Virginia has a lot of public ranges that are freely available to the public. The signs request ordinary shooter courtesy: put your fired brass in the barrel, along with shot targets, tin cans and any other trash, and try not to shoot up the wood target stands. It is the free-gun-use-friendliest state I have ever visited. Haven't been there in about five years, but I doubt it has changed.
You go to a place like that and all of a sudden you realize what America used to be.