Happened to catch an episode of Black Market with Michael K. Williams entitled Iron Pipeline and found it interesting most of the illegal gun trade began with theft from gun stores or from straw purchases. The gun runners have people who “legally” purchase the firearms for them. By definition that is a straw purchase and is illegal. I’ve been trying to think of a way to stop straw purchases, but have come up empty. Once someone decides to commit a crime by buying a firearm for someone else they must lie on their forms and the only way to stop them would be to catch them in the act. You can purchase a firearm and latter sell it to someone who can legally own a firearm, but you cannot buy it for someone else knowing they are not legally able to own a firearm. From watching the program the problem really boils down to gangs so IMO if you want to stop the illegal gun trade you eliminate gangs by declaring them terrorists and making gang affiliation so unsavory no one else wants to become a member. If you get a chance check out the episode.