A US court settlement allowing 3D-printable gun plans to be posted online has fuelled calls for a national adoption of the NSW approach to outlawing blueprints.

Key points: The court ruling would make it easier to download plans for guns that can be manufactured on 3D printers

The court ruling would make it easier to download plans for guns that can be manufactured on 3D printers Some of the simple models can be fired only once

Some of the simple models can be fired only once However, the more sophisticated weapons include metal parts and are reusable

The open-source organisation at the heart of the case, Defense Distributed, declared "the age of the downloadable gun" would begin on August 1, when it could legally post its plans for undetectable and untraceable firearms online.

However, a federal judge in Seattle issued a temporary injunction on Tuesday afternoon — this morning Australian time — to block their release.

Eight attorneys had filed a lawsuit earlier this week, arguing the 3D guns would be a safety risk.

The 3D-printed gun "Liberator" by Defense Distribution. ( Website: http://defcad.org/liberator/ )

Academics in Australia fear the release of blueprints will increase experimentation amongst so-called "tinkerers" in Australia, and NSW Police have warned even possessing the plans on a cloud service is a criminal offence.

Australian National University Professor of Criminology Roderic Broadhurst said Australia already had a home-made gun manufacturing world whose members were eyeing off 3D printer advancements.

"We can expect to see more tinkerers and more people involved who don't have easy access to firearms perhaps finding this as an opportunity," he said.

"There are enough examples now where it's gone from ideas to actual practice."

Methods for dealing with nefarious applications of 3D printing differ between states and territories.

A 2015 reform to NSW legislation created a unique offence for possessing digital blueprints for firearms, including a maximum penalty of 14 years' jail.

3D-printed weapons used for research by the New South Wales Police Force. ( ABC News: Connie Agius )

Head of the NSW Drug and Firearms Squad Detective Acting Superintendent Jason Weinstein pointed to a broad interpretation of when a person "possesses" blueprints — including when blueprints were held in someone else's computer and outside the jurisdiction.

"That is to say, that whilst it is stored in 'the cloud' one is still deemed to be in possession under the Act," he said.

He said police proactively identified persons of interest who downloaded CAD (computer-aided design) diagrams for illegal purposes.

"We continue to aggressively pursue this new and developing phenomena."

Professor Broadhurst said he believed it was time to consider the NSW law as a national approach.

"It does give you a bit more room to move from a deterrence point of view or from an investigative point of view," he said.

"You can have a search warrant for that. It gives law enforcement agencies a bit of an opportunity to intervene."

'Alarm bells' ringing

The problem of home-made weapons extends beyond pistols being produced by 3D printers from plastic, or polymers.

Professor Broadhurst said of more concern were all-in-one cutting devices that could include templates for firearms within their computers.

"This is a machine that can be literally shipped in in a box," he said.

3D-printed guns were found at a home unit in Sydney's eastern suburbs in 2017. ( Supplied: NSW Police )

Authorities would need to examine the actual software to determine if it posed a risk.

"I do think it's going to pick up pace. I think there'll be a lot more experimentation."

Acting Superintendent Weinstein said the greatest risk of 3D-printed firearms was the instability of the gun.

"There is a real potential to cause serious injury to the person holding the firearm and those in the near vicinity," he said.

A spokesperson for Federal Law Enforcement and Cybersecurity Minister Angus Taylor said: "It is a criminal offence in all jurisdictions to manufacture a firearm without a licence — this includes using 3D printing."

'Fanboy' caught by NSW law

Advertising agency account manager Sicen Sun became the first person to fall foul of the NSW legislation in February 2017.

Acting on a tip-off, detectives found imitation pistols, 3D-manufacturered Glocks and two 3D printers at his unit in Waverley, in Sydney's east.

Sun's lawyer claimed in court he was simply a science fiction "fanboy" whose hobby got out of hand.

Police claimed Sun tried to sell a gun on social media, leading to his arrest.

The Defense Distributed case began when founder Cody Wilson, a self-described anarchist, uploaded blueprints for his "Liberator" pistol in 2013.

The US State Department tried to stop the company from operating under firearm exportation laws.Wilson and a gun rights group fought back, citing two parts of the US constitution, and in June the case was dropped.

Professor Broadhurst said Australians downloaded the "Liberator" blueprints "in the thousands".

He warns similar files were likely to pop up via peer-to-peer mechanisms and in Dark Net markets.