It's my understanding that you have to register a handgun in ca. I guess I'm just not sure that I can do that if I don't have any paperwork otherwise on it.
Rob,
This is taken off a California State Q/A site;
"There is no firearm registration requirement in California except for assault weapon owners and personal handgun importers. However, you must submit a Firearm Ownership Report (FOR) Application (BOF 4542A), pdf to the California Department of Justice (the Department) for any firearm you are seeking return where no other record is on file with the Department identifying you as the most recent owner/possessor. Having a FOR application on file with the Department will authorize the return of your firearm in the event it is subsequently lost or stolen. With very few and specific exceptions, all firearm transactions must be conducted through a firearms dealer. If you purchased a handgun from a properly licensed California firearms dealer and underwent a background check via the state’s Dealer’s Record of Sale (DROS) process, a record of your handgun purchase is already on file with the Department. Therefore, it should not be necessary for you to submit a FOR application for handguns previously purchased in California. Unfortunately, this is not the case with regards to rifles or shotguns. Prior to January 1, 2014, the Department was prohibited by law from retaining DROS long gun information."
Keep your guns and enjoy them. If you decide to sell them, do so through a dealer. You will not be required to show anything- they will just fill out the transfer paperwork.