I ignore California. What is their gun policy right now? May a person own a gun? Are all guns registered in California so they know who has a gun?
I am not an expert on CA gun laws, but I can probably list a few of the egregious ones.
Rifles with removable magazines must be modified to require breaking down the gun (using a required tool) in order to change the mag. This affects more than just AR15s because it's
all rifles. Magazines can be no larger than 10 rounds, rifles and pistols. I have no idea about the requirements for transporting a firearm. CA does not have CCW reciprocity.
There's "owning" and "carrying." Carrying concealed requires a permit, and CA is a "May Issue" State, so every time a County elects a Democrat Sheriff, all CCW are allowed to expire because they won't approve anybody but their best buddies. I don't know if a Permit to Purchase is required (like in IL).
Yes, all guns are registered in California (not sure about antiques). They go the extra step of matching up the list of registered gun owners with the Medical Marijuana card holders. If they get a match, Police will eventually show up at your door to disarm you. They also keep tabs on the VA's psych patients so the Police can knock on a door and confiscate the weapons right away with no prior hearing.