A mechanical engineering student spent several months putting together the very first 3D-printed revolver. James Patrick created PM522 Washbear, which fires up to eight .22LR leads between reloads. 

This pepperbox revolver, however, was not totally 3D-printed. Patrick also added a metal firing pin, steel rods and elastic bands. The detectable metal was added to comply with gun regulations. It has yet to be seen, though, if this is sufficient for the gun to be deemed legal.

Patrick used heavy-duty nylon and ABS plastic for the 3D-printed gun. Apart from being safe, ergonomic, sturdy, and easy to use, Patrick wanted the gun to have some specific features.

First, it must be 3D-printable with a Rockstar Max or a smaller 3D printer. Second, it must have a double-action or double-action-only mechanism. Third, it should have the capacity to fire a caliber of .22LR in no less than four shots. Finally, it has to feature few non-printed parts.

"That's a pretty long shopping list," he says. "I spent a lot of nights sketching on paper and modeling in Autodesk Inventor and came up with this PM522 Washbear revolver."

Patrick also discloses how he built the PM522 Washbear revolver.

"Feel free to distribute these files, so long as attribution is given," says Patrick.

He goes on to say that it is a necessity to always obey all state, federal and local regulations.

"Use this information at your own risk and responsibility," he adds.

In November, New South Wales, Australia passed an amendment prohibiting the ownership of 3D-printed gun blueprints. However, the ruling excuses those who own 3D-printed gun blueprints who use them for research or public benefits (such as police officers).

Check out what Patrick's 3D-printed gun can do in the video below.