The United States Undetectable Firearms Act of 1988 (18 U.S.C. § 922(p)) makes it illegal to manufacture, import, sell, ship, deliver, possess, transfer, or receive any firearm that is not as detectable by walk-through metal detection as a security exemplar containing 3.7 oz (105 g) of steel, or any firearm with major components that do not generate an accurate image before standard airport imaging technology.
This is on the defcad website. All of the schematics follow this law.
The virgin NRA member vs the Chad defense distributed member
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