A masked man, armed with a semi-automatic handgun, pointed his gun at the gas station clerk and demanded money. When the clerk refused, the robber pulled the trigger.Fortunately for the clerk, the bullet bounced off inches of ballistic glass separating the employee from the would-be thief. Miami-Dade police said the robber kept trying to reach the register as the 54-year-old clerk called police to the gas station at 11191 SW 176th St. around 3:30 a.m. Sunday.By the time police arrived, the failed robber had fled. No one was injured and nothing was stolen, but police are looking for the man, who was wearing a black hoodie, a black face mask, black gloves, red shirt, black pants and black sneakers.