Here in the state of walking Cuckoo-Cuckoo clocks, free legal advice is as accurate as the electricity being on.
Ask you question here;
https://www.calguns.net/calgunforum/index.php
There's a legal section you can search and some incredibly bright people. Might be worth a phone call to a gun lawyer because if you get it wrong here - and it's easy - you will loose property and liberty for zero gain.
The laws can and do vary by county and even city. Typically, rural area are normal and people are mostly cool.
Store you weapons in a locked container (trunk works) and the ammo should not be accessible. Don't get caught with a weapon in a state park. I've never seen a law that says you can have one in a national park, either. Right now, almost everything in the woods is closed or strictly restricted. Watch your fires of any type. Some of the bigger parks (Yosemite for example) are full of thieving dirtbags. Watch your valuables. Don't leave them exposed in a locked car. I know people who had their mountain bikes stolen from their camp while they slept.
I do know bringing ammo into the state, for me, is a felony. I've never looked into from your perspective. If I shoot in Nevada, I buy ammo there, use it all, and come back empty.
Rimfires are often exempt from the stupidity. Lever guns can be centerfire with a tube magazine.
People in bigger cities and their burbs, I would consider gun-unfriendly so watch you conversations on the subject. Not all of them are, but the zealots are nuts.
Have fun!