If Samuel were still a betting man, he'd lay money that he'd never see the gun again. Winchester would keep it, cavalier about what he held and seeing its soul-killing power as a boon. He'd be dead within a year, but that was his own damnfool choice, not Samuel's.
Samuel's damnfool choices had begun with a blow from a mermaid, which gave him an aversion to water, and they'd ended with a kiss from a golden-eyed girl, which gave him cursed and necessary knowledge.
Rendering a demon to its components and imbuing its essence in metal and wood left nothing to fear.