If you "mailed" a handgun, then that is part of the issue.
Handguns must go FedEx or UPS for the non-FFL guys like myself.
Other than that, FFL dealers can select to do transfers following what ever rules they see fit.
When the ATF looks at their log book, the FFL holder may choose the simplicity of having FFL numbers written in on the "Acquisition" side.
Most FFL dealers are running scared of whizzing off the ATF folks and having their FFL jerked thus losing their livelihood.
