Man sentenced after attempting to manufacture a 3D-printed machine gun

The case of a man sentenced after trying to build a 3D printed machine gun is not a one-off oddity, it is a snapshot of how fast cheap tech is colliding with hard firearms law. A desktop tool that many of us use for printing duck decoys or scope mounts became, in his hands, the backbone of a home workshop for automatic weapons. The courts answered with a 15 year term, a signal that when hobby gear crosses into gun manufacturing, prosecutors will treat it like any other serious weapons crime.

I have spent enough time around both guns and gearheads to know how thin that line can look from the workbench. This case, and several others like it, show how investigators now track digital footprints, payment histories, and printer output the same way they once followed serial numbers and shell casings. If you care about firearms, hunting, or even basic shop freedom, it is worth understanding exactly where that line sits and how quickly it can be crossed.

The man, the sentence, and what the court actually decided

At the center of the story is Robert Adamski, who set up a 3D printer in his East London home and started turning out parts for what investigators say was a sub machine gun capable of automatic fire. When officers moved in, they found the printer actively producing the penultimate component of a 9 mm semi automatic rifle, along with other parts that together could form a compact automatic weapon, and that is what ultimately drove the 15 year sentence, with 15 years in prison and two years on licence, reported in detailed coverage of the sentence. Prosecutors did not need a completed, test fired gun on the table, they needed to show a clear intent to manufacture a prohibited automatic firearm, and the half finished rifle, CAD files, and printed magazines did that job.

Separate reporting on the same case describes how counter terror officers had already flagged Adamski after finding extremist material and racist content on his devices, then tied that digital trail to a payment for a 3D printer in June 2024 and to files for a sub machine gun design stored on his computer the previous month, details that match the account of the attempt. Another summary of the same prosecution notes that the man who tried to make a 3D printed machine gun was jailed for 15 years after that counter terror investigation, reinforcing that this was treated as a terrorism linked weapons case, not a simple firearms licensing issue, as laid out in the description of the jail term.

How counter terror police built the case

From a law enforcement standpoint, what stands out is how early and how thoroughly counter terrorism officers moved once Adamski came onto their radar. One detailed account explains that he was first identified through online activity, then taken into custody while officers searched his home, where they found the 3D printer, printed components, and extremist material that showed a clear hostility towards ethnic minorities in London, a pattern described in the official summary of the terrorism offences. That combination of ideology, tools, and technical progress toward a working gun is what turned a hobbyist setup into a national security concern in the eyes of investigators.

The Metropolitan Police later laid out how their specialist counter terrorism unit monitored his purchases, including the 3D printer itself, and then moved in when they believed he was close to producing a complete and viable firearm, a sequence described in their own account. When officers entered his East London address, they found the printer mid job on that penultimate rifle component, along with already printed magazines and other parts, a scene that matches the description of how The Metropolitan Police discovered a printer actively producing a 9 mm semi automatic rifle component, as set out in the report on the East London raid.

Far right ideology and why it mattered in sentencing

Ideology is not a side note in this case, it is part of why counter terror units, rather than a standard firearms squad, took the lead. One detailed summary describes Adamski as a right wing extremist who had collected racist material and content praising violence, and who was caught trying to use a 3D printer to build a sub machine gun, a characterization that appears in the report that credits the Metropolitan Police. Courts in the United Kingdom have wide latitude to treat weapons offences more harshly when they are tied to extremist intent, and that appears to be what happened here.

Another account of the same sentencing notes that investigators recovered several already printed firearm parts, including a magazine that could hold 25 cartridges, and that these parts were considered alongside the extremist material when the judge weighed risk to the public, a detail that lines up with the description of a magazine that could hold 25 cartridges in the report that again credits the 25 round magazine. When you put that together with the earlier counter terrorism summary about his hostility toward ethnic minorities, it is clear the court was not only punishing a technical firearms breach, it was responding to the risk of a politically motivated attack.

What police actually found in the flat

For anyone who has ever tinkered with 3D printed gun parts, the inventory from Adamski’s flat reads like a checklist of what not to have on your bench. Officers found the printer itself, spools of filament, and multiple printed components that together formed most of a 9 mm semi automatic rifle, along with a magazine capable of holding 25 rounds, a scene that matches the description of several already printed firearm parts, including a magazine capable of holding 25 rounds, recovered by Investigators. They also seized digital files that mapped out the rest of the build, which prosecutors used to argue that finishing the weapon was a matter of time, not theory.

One official summary notes that the man had been found guilty of terrorism offences linked to his attempt to make firearms using a 3D printer, and that officers searching his home found not only the printer and parts but also extremist documents and material that praised violence, as laid out in the description of the guilty verdict. Another report on the same case emphasizes that the printer was actively producing the penultimate component of the rifle when The Metropolitan Police entered, and that the man had bought the 3D printer in June 2024, details that match the account of how The Metropolitan Police discovered a printer actively producing that component and traced the purchase of the 3D printer in June 2024 in the East London account.

How this fits into a wider pattern of 3D printed weapons

Adamski’s case is part of a broader pattern that has police and prosecutors on both sides of the Atlantic paying close attention to 3D printed and so called ghost guns. In Seattle, a 26 year old man was sentenced in U.S. District Court to 27 months in prison after being arrested with twenty ghost guns and more than 100 Glock switches, along with two silencers, a haul described in detail in the federal summary of the Seattle case. Many of those guns were homemade, with no serial numbers, and some involved 3D printed components, which is exactly what worries regulators.

In Idaho, a 48 year old Pinehurst man with a prior felony conviction was sentenced to more than six years in federal prison after being caught with multiple firearms, including ghost guns and other homemade firearms that were often 3D printed, a fact pattern laid out in the report from COEUR d’ALENE, Idaho, on the Pinehurst man. That same case was highlighted by a NonStop Local Digital Producer, who noted that the 48 year old would be prohibited from owning firearms in the future, a point spelled out in the follow up that credits a Local Digital Producer. Put together, these cases show that once a homemade gun crosses into functional territory, courts are treating it like any other illegal firearm, regardless of whether it came off a factory line or a hobby printer.

Lawmakers and prosecutors scramble to keep up

As these cases stack up, lawmakers are trying to close the gap between old statutes and new tools. In Washington state, for example, Attorney Todd Greenberg has backed a push to curb 3D printed ghost guns, pointing to manufacturing operations in the Chinatown International District and warning that people are using printers, CNC machines, or any other means to turn out untraceable weapons, a concern he laid out while discussing how a federal judge cracked down on one such operation, as described in the report quoting U.S. Attorney Todd Greenberg. State legislators there are now looking at new rules that would specifically address 3D printed frames and receivers, not just traditional gun parts.

That political push has filtered into local coverage too, including an Olympia Watch segment that framed the debate as an effort to crack down on 3D printed guns by updating state law to match what prosecutors are already seeing on the ground, a framing that appears in the Olympia Watch report. When you line that up with the Seattle ghost gun case and the Pinehurst prosecution, you can see a pattern: federal and state authorities are no longer treating 3D printed guns as curiosities, they are treating them as a core part of the illegal firearms landscape and adjusting both charging decisions and proposed legislation accordingly.

Other recent machine gun and ghost gun prosecutions

Adamski is not the only person to learn the hard way that building or selling automatic weapons, whether printed or machined, will bring serious time. In Texas, a machinegun maker from Round Rock was sentenced after selling a converted weapon to an undercover ATF agent, a case that involved not only the machine gun itself but also accessories like sights, lights, and lasers, as laid out in the report on the Round Rock case. That defendant did not rely on 3D printing, but the legal principle is the same: once you are in the business of making or selling machine guns without the right paperwork, you are squarely in federal felony territory.

The same Round Rock case has been cited again in follow up coverage that stressed how the machinegun maker from Round Rock was caught after selling to an ATF agent and that the weapons included various accessories, reinforcing how undercover operations are now a standard tool in these prosecutions, as noted in the additional report on the machinegun maker. When you compare that to Adamski’s situation, the common thread is that investigators are willing to invest serious resources, from undercover buys to digital forensics, whenever they see someone edging toward automatic weapons, whether the parts are milled steel or layered plastic.

What this means for gun owners, tinkerers, and the law

At the same time, other coverage of the far right extremist case notes that Tuesday’s sentencing credited the Metropolitan Police and PA Wire for images of Adamski’s desk, covered in parts and extremist material, and that the court treated his 3D printer setup as part of a broader terrorism risk, a framing that appears in the report that again credits the Metropolitan Police. For law abiding shooters and makers, the takeaway is straightforward: stay well inside the law, know exactly how your jurisdiction defines a firearm or a prohibited part, and understand that once you start printing or machining components that can readily be turned into an automatic weapon, you are stepping into the same legal territory that put Adamski and others behind bars.