Which type of gun cannot be entered into the NCIC Gun File?

The reason a BB gun cannot be entered into the NCIC Gun File is that the NCIC primarily focuses on firearms that are classified as "real" guns, which are capable of firing bullets and are designed for use in the traditional sense of firearms. BB guns, on the other hand, typically fire non-lethal projectiles (BBs) and are often classified as air guns or toys rather than actual firearms. As such, they do not meet the criteria established for entry into the NCIC Gun File, which is intended for tracking firearms that pose a legitimate threat to public safety or are involved in criminal activities. The other types of guns listed—shotguns, handguns, and revolvers—are recognized as traditional firearms and can be legally owned and used for various purposes, including hunting and personal protection, thus making them eligible for inclusion in the NCIC database.