A group in the United States has test fired the world's first working gun to be made by a 3D printer.
The technology works by building up layer upon layer of material - typically plastic - to build complex solid objects.
Defense Distributed said it will make the blueprints available on the internet.
The BBC's science reporter was given exclusive access to the tests in Austin, Texas.
The gun was made on a 3D printer that cost $US8000 from eBay. It was assembled from separate printed components made from ABS plastic - only the firing pin was made from metal.
Law student Cody Wilson, 25, said: "I think a lot of people weren't expecting that this could be done."
The BBC reports 3D printing has been hailed as the future of manufacturing. The technology works by building up layer upon layer of material - typically plastic - to build complex solid objects.
The idea is that as the printers become cheaper, instead of buying goods from shops, consumers will instead be able to download designs and print out the items at home.
Mr Wilson told the BBC: "There is a demand of guns - there just is. There are states all over the world that say you can't own firearms - and that's not true anymore.
"I'm seeing a world where technology says you can pretty much be able to have whatever you want. It's not up to the political players any more."
Asked if he felt any sense of responsibility about whose hands the gun might fall into, he told the BBC: "I recognise the tool might be used to harm other people - that's what the tool is - it's a gun.
"But I don't think that's a reason to not do it - or a reason not to put it out there."
To make the gun, Mr Wilson obtained a manufacturing and seller's licence from the US Bureau of Alcohol, Tobacco, Firearms and Explosives.
The agency told BBC News that the 3D-printed gun was legal in the United States as long as it was not a National Firearms Act weapon (an automatic gun, for example).