The only non-printed piece is a common hardware store nail used as its firing pin.

FORBES: Meet The 'Liberator': Test-Firing The World's First Fully 3D-Printed Gun

The Liberator is comprised of 16 interchangeable pieces, with a nail for a firing pin.

CNN: Video shows test firing of 3-D-printed handgun

"Basically, it's still a pipe and it's got a firing pin at the bottom, " Trevithick said.

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It was assembled from separate printed components made from ABS plastic - only the firing pin was made from metal.

BBC: Working gun made with 3D printer

The government may simply insist that 3D printer manufacturers install software that prevents printing of a hollow cylinder of a certain size, a firing pin, or a certain type of spring.

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The Liberator fired a standard .380 handgun round without visible damage, though it also misfired on another occasion when the firing pin failed to hit the primer cap in the loaded cartridge due a misalignment in the hammer body, resulting in an anti-climactic thunk.

FORBES: Meet The 'Liberator': Test-Firing The World's First Fully 3D-Printed Gun

Earlier this week Wilson posted a video online showing a single shot being fired from "The Liberator, " a plastic handgun that, with the exception of a metal firing pin and a piece of metal included to comply with the Undetectable Firearms Act, was assembled entirely from parts made with a 3-D printer.

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