Do I have to be a member to shoot? Am I allowed to bring my own ammo and what’s the biggest caliber allowed?

YES!

No you don't have to be a member to shoot and the biggest caliber idk.

You can bring your own ammo they will see if it's meet there condition I'm not sure on the biggest well 12 guage rounds are pretty big thou and know you don't have to be a member to shoot just sign up your wavier form to be added into there system then get to the next process before you shoot....

All Pistol calibers are allowed that I know of. Shotguns they only allow 12 gauge slug/00 Buck. Rifle I believe most calibers are accepted that I know of as they have a 50 BMG you can rent but to be sure the ammo has to be maximum velocity up to 3,388 fps & a maximum energy up to 3,600 ft/lbs. If the ammo will surpass those then it isn't allowed. Also no steel core ammo is allowed.