WALKERSVILLE — A gun rights group is taking aim at the town to try to force a change in its firearm restrictions. The Second Amendment Foundation, based in Bellevue, Wash., formally demanded that Walkersville repeal a ban on shooting and carrying loaded guns within town limits. "It has come to my attention that the town of Walkersville purports to regulate firearms, which violates of state law," Alan M. Gottlieb, foundation president, said in a March 26 letter. The town charter bans shooting "a rifle, air rifle or air gun of any kind ... a bow and arrow, slingshot, shotgun, gun...