The following tutorial will show you around the part 478 landing page.
27 CFR Part 447
Importation of Arms, Ammunition and Implements of War
27 CFR Part 478
Commerce in Firearms and Ammunition
27 CFR Part 479
Machine Guns, Destructive Devices, and Certain Other Firearms
27 CFR Part 555
Commerce in Explosives
27 CFR Part 646
Contraband Cigarettes
27 CFR Part 771
Rules of Practice in Explosive License and Permit Proceedings
Effective date is the date this part was last amended
The evidence specified in § 478.40(c), relating to transactions in semiautomatic assault weapons, shall be retained in the permanent records of the manufacturer or dealer and in the records of the licensee to whom the weapons are transferred.