On April 20, 2021, a leaked ATF document titled “Definition of ‘Frame or Receiver’ and Identification of Firearms” revealed the Biden administration’s plan to introduce stricter firearm regulations. The proposed rules would expand the ATF’s authority, potentially restricting gun rights, particularly the ability to legally build firearms.

In response, Defense Distributed proactively commissioned Hall Precision LLC (now operating as G100) to design the G0, a fully DIY 0% pistol compatible with the G19.3 ecosystem. This G0 FCU can be fully milled on the Ghost Gunner CNC, effectively sidestepping the proposed regulatory changes.

Independently, Hall Precision recognized that a 100% completed (non-DIY) version of the open source G0 FCU could be manufactured under an FFL-07 and sold to the general consumer market. This led to the creation of the G100 120 series, allowing anyone to enjoy the benefits of a modular receiver without needing to invest in CNC milling equipment.

The G100 platform offers endless customization. Users can choose from our expanding selection of expertly crafted grip and PDW options, and our designs are available for download, 3D printing, remixing, or can serve as inspiration to create entirely new designs from the ground up.