Trayvon Martin Case Felt at N.R.A. Convention Daniel Acker for The New York Times A visitor at the National Rifle Association's annual convention in St. Louis, where gun owners expressed a reluctance to jump to conclusions in the killing of Trayvon Martin. LOUIS - Inside the seven-acre showroom at the National Rifle Association's annual convention here during the weekend, firearm enthusiasts filtered in and out of the sea of booths displaying handguns and the holsters designed to hide them. Eager to explain the benefits of carrying a concealed weapon, hikers discussed how they feared bandits more than bears on the trail. Aging men rattled off hypothetical situations requiring self-defense; the details varied, but all involved some version of a younger, more muscular aggressor. Yet with the gun lobby gathering just days after George Zimmerman was arrested in the fatal shooting of Trayvon Martin, an unarmed teenager in Florida, there was a new potency to such contingencies as many gun owners wait for more evidence about the killing to emerge. "People here are definitely thinking and talking about it," said Terrence Mayfield, 61, who has a permit to carry a concealed firearm in Florida. This whole thing rests on who threw the first punch. Either the gun saved Zimmerman's life or we had a cowboy, someone who thought because he had a gun things could escalate. There are still questions about exactly what happened the night Mr. Martin died. The answers may determine whether Mr. Zimmerman, a neighborhood watch volunteer who told the police that he had pulled the trigger in self-defense, will be protected by Florida's version of the Stand Your Ground laws that states across the country have enacted to grant broad rights to people who use deadly force to defend themselves. A special prosecutor appointed to the case charged Mr. Zimmerman with second-degree murder last week. Other than a Saturday speech that accused the news media of sensationalized reporting, N.R.A. officials have not commented on Mr. Martin's death. But interviews with almost two dozen members over the weekend showed that some remain nervous about how the controversy might affect the future of Stand Your Ground statues across the country, which have come under scrutiny since the shooting on Feb. 26. "The danger is potentially reversing the laws that it's taken us decades to get in place and the further erosion of my rights," said Mr. Mayfield, an Air Force veteran who served in the Persian Gulf war of 1991. He offered a hypothetical confrontation to explain why he carries a gun: "I'm a 61-year-old fat guy with a bad back with a little bit of shrapnel in my leg. There's no way in hell I'm going to be able to run away from a 20-year-old. Many of those interviewed expressed a willingness to give Mr. Zimmerman the benefit of the doubt, accusing others of rushing to judgment before all the facts are revealed. At the same time, they were pleased to see that the shooting was being investigated. "Zimmerman was a neighborhood watch guy trying to defend his neighbors," said Marian Johnson, 69, from South Dakota. I'm sure he didn't set out to see what happened happen. I just hope they're fair to both sides. Kent Hawkins, 55, who lives in Kentucky and has been a member of the N.R.A. on and off since he was 12, said: "I wasn't there, so I can't say. People are jumping to conclusions and shaping it into whatever they want it to be. But others have begun to distance themselves from Mr. Zimmerman, offering up the familiar slogan - "Guns don't kill people, people kill people" - to emphasize that one shooting should not overshadow the fact that millions of law-abiding gun owners in the United States have never had a violent altercation. "I don't think you'll find anyone here who would promote vigilante justice," said Preston Haglin, 60, from Missouri. Greg Moats offered another assessment. "If Zimmerman acted out of line, there are laws in place to deal with that," said Mr. Moats, 59, from Kansas. He added that he did not think the case should be a gun issue in the first place. "There's nothing that the anti-gun groups wouldn't do," he said. There's no national disaster they wouldn't exploit. They can manufacture fuel for whatever argument they want. Still, Martha Gagliardi, 62, said she worried that any new evidence against Mr. Zimmerman could provide additional arguments to gun control advocates. A member of the gun lobby for three decades who lives in upstate New York, Ms. Gagliardi said her Second Amendment right to bear arms had become an extremely personal issue, requiring no theorizing about imaginary attackers, ever since she was robbed at gunpoint years ago in the driveway of her home in Queens. "That's when I moved," she said. That's when I got my gun license. I never want to feel that helpless again.