HR4221-119

What This Bill Does

The Undetectable Firearms Modernization Act updates the federal ban on undetectable firearms for modern manufacturing and screening technology. It changes the detectability test so all parts other than major components cannot lack detectable material, updates x-ray language to detection devices commonly used at airports, defines major components as the slide or cylinder, frame or receiver, and for rifles or shotguns the barrel, and defines detectable material by reference to a magnetic field equivalent to 3.7 ounces of 17-4 PH stainless steel. It also covers prototypes, removes outdated sentence language, and limits exceptions to firearms possessed or controlled by the United States or made, imported, possessed, transferred, received, shipped, or delivered by licensed manufacturers or importers under an existing U.S. contract.

Who Benefits and How

Airport security screeners benefit because the bill updates firearm detectability rules for modern detection devices. Law enforcement officers benefit because prototypes and major components must meet clearer detectability standards. Communities concerned about 3D-printed firearms benefit from a ban better matched to modular and homemade firearms. Federal agencies benefit from preserved exceptions for government-held firearms and government-contract production.

Who Bears the Burden and How

Firearm manufacturers must ensure major components and parts satisfy the updated detectable-material requirements. 3D-printed firearm makers lose room to exploit detachable grips, stocks, magazines, or prototype loopholes. Licensed importers must fit government-contract exceptions if handling otherwise covered undetectable firearms. Gun hobbyists experimenting with prototypes face expanded statutory coverage.

Key Provisions

• Updates the undetectable-firearms test to require detectable material in firearms and major components.
• Defines major components to include slides, cylinders, frames, receivers, and rifle or shotgun barrels.
• Defines detectable material by magnetic-field equivalence to 3.7 ounces of 17-4 PH stainless steel.
• Extends coverage to prototypes and narrows exceptions to U.S. possession or licensed government-contract activity.