I'll give it a shot.

I'm incorporated as an S corp for my rental properties...

years ago an llc or limited liability corporation would reduce your exposure to liability suits, but changes in law and precedent have pretty much nullified that advantage from what I understand from my accountant.

basically incorporating seperates personal assets from corporate assets, so in your case I would incorporate though all officers of the corp can and will be sued if any of you do something stupid.

In most states the answer will be that the person doing the screw up or involved can be sued personally, corp or not, but the entity will serve to protect the individual officers and agents who were not directly involved from suit against their personal property. (the protection level will vary from state to state).

Up here a non-profit would run about 1-1.5k, with another .5 per year to keep things going properly, for a few guys running a club. Also plan on at least .5-1k to have your insurance contracts reviewed by the lawyer. You guys will want to buy at least 10 mil for the corp and 5 mil umbrella for each officer/agent/range officer. That will cost bucks, and the insurers have gotten worse about writing screwed up coverage terms. You guys will also need agreements with the range officers/workers for events so they can be insured, that costs to draft model agreements you can use.
Anything unusual in terms of what the club does, or any substantial property owned, or any fund rasing, add at least 1k for each event...
if you want to try for tax free, or a PAC, plan on going 20k for each, and another 5-10k every few years thereafter.