Berlin / Halle (AP) - The weapons of the assassin of Halle repeatedly failed. On his video, which Stephan B. streamed live into the internet, he was repeatedly cursed loudly. "What'n wrong? My face, man, lad! Oh, shit. "

If, above all, the two self-made submachine guns would not have intervened again and again, Hall would probably have been much more victims in the bloody murder of Halle.

In his manifesto, uploaded by the offender on the website Kohlchan - the German counterpart of the controversial US platform 8chan - he described in detail his arsenal. Among them were two submachine guns designed by the British weapons activist Philip Luty, who wanted to demonstrate for the free possession of firearms.

While the "Luty SMG 9mm Parabellum" from the Halle assassin was made entirely of metal parts, the second Luty submachine gun was also made with plastic parts from the 3D printer. The investigators have discovered a printer in the living quarters of Stephan B. The perpetrator did not only rely on high-tech, but also on very simple technology: his equipment included a so-called slam-bang shotgun, which consists in the core of only two tubes and a simple trigger.

Weapons from the 3D printer have been a topic for years: In 2013, the Texan Cody Wilson put the plans for a weapon from the 3D printer into the net. The gunman and activist was supported by the weapons lobby organization Second Amendment Foundation. His single-handed plastic pistol "Liberator" (Liberator) sparked worldwide fears: Not only because virtually anyone can get a weapon with the digital blueprints, but also because the plastic gun is not recognized by classic metal detectors at security gates.

The 3D printer technology makes it much easier to build weapons yourself. Compared to the self-made weapons made of sheet metal and steel weapons from the 3D printer can be built without manual skills. The machines "print" the weapon parts in a layered printing process made of plastic to a tenth of a hundredth of a millimeter, so they can work much more precisely than laymen who do not have a traditional gunsmith training.

So far, the plastics used have generally not been able to withstand the high pressure created when firing a cartridge. Therefore, the gunsmith scene relied on hybrid weapons that combine metal parts for barrel and chamber with plastic parts for the magazine or the barrel of the weapon. The "Plastic Luty" of the Halle assassin was also a hybrid model made of plastic and metal.

However, it is foreseeable that in the future even more complex weapons can be manufactured completely in 3D printers. The plastics used withstand ever higher temperatures and withstand greater pressure than previous generations. Blueprints and 3D print templates for the 3D printer guns circulate on the Internet. Interested parties do not even have to move to "darknet", but will also find what they are looking for on the open web.

Manufacturers of 3D printers no longer want to tolerate the misuse of their devices by guncarves and extremists. So the leading French manufacturer Dagoma fights with manipulated blueprints against the production of firearms. "The weapon files that we change look just like the original, but the finished printed products are not useful," said Dagoma co-founder Matthieu Régnier. These "false" firearms models have already been downloaded 13,000 times.

The scene will also succeed in the future to track down building plans for weapons from the 3D printer on the net, which were not manipulated - also because the radical-liberal US gunman Cody Wilson always manages to prevail against prohibition applications. In June 2018, the US government under President Donald Trump made a settlement with Wilson, which suspended a ban on the term of office of US President Barack Obama. However, several US states are trying to stop the spread of the 3D blueprints.

Since 2018, Wilson has been selling kits, software and a special CNC machine for those weapons that are not coming from the printer through a separate company. On offer is a kit for a semi-automatic assault rifle, which is modeled after the AR-15. For example, the gunmen killed in Parkland and Las Vegas with the AR-15.

British weapons activist Philip Luty, who delivered the weapons templates in Halle, did not live to see the 3D printer era. He died of cancer in 2011 shortly before he had to answer to a court in the UK for a terrorism lawsuit.