Actually, that’s prohibited by the law. You would want to make sure the date and place of purchase of the ammo can’t be traced.
Discard the receipts and boxes.
Make them prove it.
Won’t happen.
It may be prohibited by California law but nothing to prevent someone from loading up on ammo at a Az or Nevada gun show!
What is California going to do? Put road blocks up on the interstates to check for fruits and vegetables and AMMO?