I think you have to be sponsored by a current member to join. If you know someone it is a good deal. Something like $30 a year, and you can use the ranges anytime.
I heard about it through a friend. We were talking about 300yd ranges that aren't too far away from me in Bel Air. He's not a member there but said they may have one and it was worth looking into. Figured I may find the answers here