thumper n. a grenade launcher; (hence) a gun known more for its power or noise than for its precision; any gun. (source: Double-Tongued Dictionary)
thumper n.— «That banger’s thumper is a double-deuce, and he packs a gauge. Translation: That gang member’s pistol is a .22, and he carries a shotgun.» —“Gang Slang Police Compile New Glossary Of Street Talk” by Peter...
gun-grabber
n.— «(article title)» —“Letter to a Gun-Grabber: The Wrath To Come” by Victor Milan The Libertarian Enterprise Dec. 1, 1996. (source: Double-Tongued Dictionary)