Richard Dyke of Windham is a tough advocate for his business and the gun-manufacturing industry. He's also a well-connected one. And Dyke, owner of Bushmaster Firearms Inc., is using as much congressional influence as he can muster these days to fight what he says are direct threats to his industry's survival: civil lawsuits. Bushmaster has been sued because it made the assault rifle allegedly used by the "beltway snipers" in the Washington, D.C., area last year. It wasn't the first such lawsuit against the industry. But he hopes it is the last. Dyke, a Republican fund-raiser with ties to U.S....