When I lived in NJ under Florio's "assault weapon" ban, I proudly purchased 20- and 30-round mags at PA gun shows and brought them back home. If I lived in CA, I'd refuse to turn in any unregistered bullets (or loaded ammo containing such bullets), and I'd make it a point to go outside of the state to buy more of them.
Gunowners should have massive protests, with each one bringing a 50-round box of ammo with them. F'em - if they want to enforce the law, let them throw a million people in jail.
Fortunately, I live in TX now. Somehow or other, I just don't see anything gun-related being banned here, not with 30 million + guns in the state. But having lived in an oppressive socialist dictatorship once (the PRNJ), I have great sympathy for gunowners in CA.
Never even caring that the "law" is illegal to start with. It not only violates the bill of rights, but the rights of all free men.