ATF Q&A: A&D Books

The information required to be entered refers to the “types” of firearms as defined by 27 CFR 478.11 and 479.11.  Types such as pistol, revolver, rifle, shotgun, frame, receiver, pistol grip firearm, silencer, any other weapon (AOW) etc., are all acceptable.  Entries such as semi-automatic, bolt, lever, etc., are not types of firearms and are not acceptable in the type of firearm field.

For more information on this question, please see this article: A&D Entries for Type of Firearm