Report of working 3D printed gun

Popular Science’s John Robb reports on a person who claims that his 3D-printed pistol can successfully fire live ammunition, though not with total reliability. The same person then went on to print a working AR-15 rifle (this is a substantial advance on last year’s account of a 3D printable AR-15 automatic conversion kit. This event has raised something of a crisis for Thingiverse, the online repository for 3D printable meshes, which is contemplating whether it will host files that can be printed into “weapons.”