Someone let a group of trigger-happy gun-toters near a 3D printer, and they managed to print off a gun [2]. Are we on the verge of guns for the masses?

Well not really, for two reasons. Firstly, the prototype gun doesn't work too well: breaking apart after just 6 rounds. This is an early version, and will no doubt be improved, but it has a long way to go. Here's a video of the first test, which happened this week:

Secondly, the whole gun isn't 3D-printed. Only the lower receiver is  - although according to the Gun Control Act [3], this part is regulated as if it was the gun itself. Extreme Tech [4] writes:

In short, this means that people without gun licenses — or people who have had their licenses revoked — could print their own lower receiver and build a complete, off-the-books gun. What a chilling thought.

Not that chilling, actually. 3D printers are not like paper printers. They are large, expensive pieces of industrial machinery, and for now, are solely used in factories.

Jon Evans at Techcrunch writes [5]:

You won’t see many home printers... At least not for a very long while. It just doesn’t make economic sense.

If you already own a gun factory, it may make sense to replace some of the machinery, eventually, with a 3D printer, but 3D printers wont be "democratising gun manufacture" just yet.