Federal · 119th Congress

HR4221 Undetectable Firearms Modernization Act

Direction

Firearms weapon accessory restrictionsAI label

Restricts gun access model confidence 90%

Updates the definition of undetectable firearms and detectable material, and expands the prohibition to include prototypes and changes the detection standard, so more restrictions on making or possessing undetectable firearms.

Section 922(p) of title 18, United States Code, is amended-- (1) in paragraph (1)-- (A) in subparagraph (A), by striking ``grips, stocks, and magazines, is not as detectable as the Security Exemplar, by walk-through metal detectors calibrated and operated to detect the Security Exemplar'' and inserting ``all parts other than major components, does not contain detectable material'';

✓ Quote verified word for word in the bill text

Firearms otherAI label

Expands gun access model confidence 80%

Broadens the exemption from the undetectable firearms prohibition for government and certain contracted firearms, so fewer restrictions on those specific firearms.

in paragraph (5), by striking ``shall not apply to any firearm which'' and all that follows and inserting the following: ``shall not apply to-- ``(A) any firearm received by, in the possession of, or under the control of the United States; or ``(B) the manufacture, importation, possession, transfer, receipt, shipment, or delivery of a firearm by a licensed manufacturer or licensed importer pursuant to an existing contract with the United States.''.

✓ Quote verified word for word in the bill text

Introduced (completed)
Committee
Passed one chamber
Passed both
President
Law

Stage: Committee · step 2 of 6

Last action: 2025-06-27: Referred to the House Committee on the Judiciary.
Filed: 2025-06-27
Committee: Judiciary Committee
Sponsor: Madeleine Dean D

Read official text (Introduced in House)Legislature page LegiScan

Why the model tagged it this way: The bill amends the Undetectable Firearms Act to update and tighten the prohibition on firearms that lack detectable material (including prototypes), while expanding the exemption for U.S. government and certain contracted firearms.

Related bills

HR9548 Blair Holt Firearm Owner Licensing and Record of Sale Act of 2026Restricts gun access Restricts gun access Committee
S4921 Blair Holt Firearm Owner Licensing and Record of Sale Act of 2026Restricts gun access Restricts gun access Committee
HR9009 Firearm Freedom Act of 2026Expands gun access Committee
HR9003 Keep Illegal Handguns Out of the Mail Act of 2026Expands gun access Committee

Text versions

Introduced in House 2025-06-27

History (3 actions)

Date	Chamber	Action
2025-06-27	Libra	Introduced in House
2025-06-27	Libra	Introduced in House
2025-06-27	House	Referred to the House Committee on the Judiciary.