doesn't seem to be much reason to discuss it anymore? http://www.forbes.com/sites/markgibbs/2012/07/28/the-end-of-gun-control/ Given the recent appalling events in Aurora, Colorado, thereâ€™s been a renewed call for greater gun control and a ban on assault weapons. Iâ€™m in favor of tighter gun control and a ban on weapons that are unnecessarily powerful but Iâ€™m afraid that technology will soon make any legislation that limits the availability of any kinds of guns ineffective.To understand why this might happen, you need to understand a technology called 3D printing.3D printing allows you to build things that are, as the name implies, three dimensional. A few years ago 3D printers were very rare, hugely expensive, and hard to use. But as with anything that can be driven by computers, 3D printers has become cheaper and cheaper to the point where, today, you can buy a 3D printer, off the shelf, for as little $500. Using either free or low cost computer aided drafting software you can create digital 3D models of pretty much anything you can think of and, with hardly any fuss, your 3D printer will render them as physical objects.The only contraints on what you can print are that the size of the printed object (typically a maximum of 6 inches by 6 inches by 6 inches unless you spend more money on your printer ; the bigger the final object you want, the more youâ€™ll have to spend), the material printed (all of the low end printers can, at present, only print with thermosetting plastics; very high end printers can print with ceramics and metals), and the resolution of the printer (for current low end printers this is typically around 0.1mm).So, can you print a gun? Yep, you can and thatâ€™s exactly what somebody with the alias â€œHaveBlueâ€ did.To be accurate, HaveBlue didnâ€™t print an entire gun, he printed a â€œreceiverâ€ for an AR-15 (better known as the militaryâ€™s M16) at a cost of about $30 worth of materials.The receiver is, in effect, the framework of a gun and holds the barrel and all of the other parts in place. Itâ€™s also the part of the gun that is technically, according to US law, the actual gun and carries the serial number.When the weapon was assembled with the printed receiver HaveBlue reported he fired 200 rounds and it operated perfectly.