David Biddell-Portman, 30, told police he had an interest in the mechanics of guns after officers discovered two 3D-printed weapons in his bedroom wardrobe, following a tip-off from the National Crime Agency (NCA).

"They're as effective as any other gun that you might fire on a firing range or elsewhere," said Gareth Cooper, a firearms expert for West Midlands Police.

"One fires a conventional factory ammunition, so it's every bit as lethal as any other gun firing that ammunition.

"The other one is designed apparently to fire-adapted blanks, which are more variable in performance but certainly capable of penetrating 6-8 inches into human flesh."

Biddell-Portman, from Birmingham, used a 3D printer to make solid components from a digital file, assembled them and added steel parts for key components that could not be made from plastic.

Police also found bullets in his toolbox, but do not know what his intentions were.

One of the weapons Biddell-Portman made was of a model which includes "FGC" in its title, meaning "f*** gun control", the court heard.

The weapon was capable of firing live rounds and was fitted with a silencer.

Detectives discovered four weapons in Biddell-Portman's wardrobe, two of which were legal, after he ordered a legal blank firing pistol, the court was told.

They also found a rifle under his bed.

The judge described the quantity of items found as a "treasure trove of gun parts and parts for rounds".

Speaking ahead of the sentence, Detective Inspector Al Teague, from West Midlands Police, told Sky News: "Anyone who was curious enough to attempt or conspire to produce such a weapon, they'd do well to take lessons from the sentence that's been handed out to Portman today and hopefully that will send a message that the police and the courts take those matters really seriously."

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In June, a Sky News investigation found that 3D printed gun designs could easily be found online and, in the US, a mainly American online community has sprung up showcasing their creations.

But Matthew Perfect, from the NCA, said it is a growing problem for the UK too.

"At this stage, we're looking at 3D printed firearms as an emerging threat.

"It's fair to say that we've seen a significant increase in both their design, production and recoveries in the last 12 to 18 months."