It's the Washington Examiner, a RW propaganda outlet. Famous for unsupported claims like the anonymous border rancher who found prayer rugs. Owned by Christian conservative billionaire Phil Anschutz. Trump laps this junk journalism up.
Lines like "The leading indicator of gun sales jumped in August, driven in part by Americans seeking self-protection and deep concerns congressional Democrats are going to push through expanded gun control legislation..." are speculation, and no factual basis is offered beyond quotes that are all from gun sellers. It's a slanted report which is thinly disguised as straight news.