This bill amends the Internal Revenue Code of 1986 to remove silencers from the definition of "firearms" under the National Firearms Act (NFA). This change would eliminate federal registration, transfer, and taxation requirements for silencers, treating their acquisition or possession under general firearms laws as sufficient. The legislation aims to deregulate these devices at the federal level by removing them from the purview of the NFA. The bill also preempts state or local laws that impose specific taxes, marking, recordkeeping, or registration requirements on firearm silencers, beyond generally applicable sales or use taxes. Furthermore, it mandates the Attorney General to destroy all existing federal registration records for silencers within 365 days of enactment. It also modifies Title 18 to redefine "firearm silencer" and "firearm muffler" and adjusts marking requirements for manufacturers, focusing on a "keystone part" for identification.