Are 3D-Printed Weapons Really 'Untraceable'? New Study Has A Surprising Answer

Criminals have attempted to hide their illicit activities for centuries, especially when firearms are involved. It's therefore not surprising in this modern era of technology that 3D-printed weapons are poised to become a serious threat. Concerns have risen to the point that a new law proposed in California would demand every 3D printer have firearm blocking tech to prevent the creation of so-called "ghost guns". While these weapons were once believed to be untraceable, a study published in the journal Forensic Chemistry by a team of researchers is now suggesting otherwise.

The four-member research team found that some of the polymers used in the printing process can have detectable differences from one another. This is due to additives in the materials, as well as variations in the kinds of materials used. As an example, a weapon made from Polylactic Acid (PLA). a common 3D-printing plastic, can have distinct chemical differences from PLAs created by different companies or through different manufacturing processes. This means that, in some cases, one PLA source could be distinguished from another.

However, it's important to note that while this is a step forward, it's still just an initial one. Researchers are not yet to the point of being able to fully trace a 3D-printed weapon all the way back to the person that purchased the PLAs to make it. 3D-printed weapons are still as resistant to traditional tracing methods, including ballistics, as they were before. More time would be needed before this new tracing technology can be fully perfected.

As of this writing, no major law enforcement or government agency has publicly commented on the 2026 study for tracing 3D-printed weapons. However, this research is sorely needed, as USAFacts reports that the number of Privately Made Firearms (PMFs) recovered between 2017 and 2021 in the U.S. increased by over 1,000%, rising from 1,629 to 19,273. PMFs include 3D-printed weapons, which are more difficult to trace due to having no serial numbers.

The availability of files for 3D-printed PMFs has been increasing, according to Everytown for Gun Safety, which reported that easily-accessible file depositories like GitHub and Google Drive were used to host more than 1,000 unique files across 2,100 different locations in 2023 alone. These files contain the designs used to physically print the weapons. Because of their accessibility, they're a major part of the problem, as there's often not a strong barrier between the files and the users that download them.

But there's no federal law that prohibits people who are legally allowed to own a gun from making one for personal use, including a 3D PMF. However, state laws may vary, and making one in a state like California can land you in hot water with the law. The catch is that federal law requires firearms to contain enough metal to be detectable by a metal detector. Completely plastic PMFs would violate federal law; any sale of them, whether from a licensed dealer or not, is illegal.