How The World's First 3-D Printed Gun Works

Defense Distributed creates a fully functional gun, with 3-D printed plastic parts. It started with a crowdfunding project last August. Now, nine months later, the world's first 3-D printed gun is here. Announced via Forbes exclusive on Friday, the design, called the Liberator, is now available for download. Here are what the parts look like: Before making a complete 3-D printed gun, Defense Distributed tested a printed part of an assault rifle. In December, the test version fired 6 shots (out o...