Lawmakers trying to stop the production of 3-D-printed guns. But it might be too late

US gun safety campaigners have expressed their anger over Congress' failure to regulate the manufacture of 3-D printed guns. Following a multi-year legal battle, the federal government last month entered into a settlement with Defense Distributed founder, Cody Wilson. Mr Wilson rose to fame after manufacturing the the first fully 3-D printed pistol in 2013, when he was just 25.