Hold shoots for kids and their parents, hold sighting in days at your range, put on shooting demonstrations at public events so that people can ask questions on how you get those old guns to fire, and " You aren't really shooting something out of that gun are you? " or " Could that gun actually hurt someone?" They have to learn somewhere, and sometimes you have to take the show to them. We march in annual parades, firing blanks charges into the air to make noise and smoke. The crowds love it, and we always get someone coming up to us to ask how he can learn more about shooting MLs. Invite Boy Scout and Girl Scout troops to your range to earn their merit badges for shooting and marksmanship! pair each member with a child, and make sure all the kids gets a chance to shoot.
If those ideas don't get you more members, I have more.
paul