If you get “ caught” with ANY gun in California, expect to have it confiscated until you can PROVE it is yours. I heard some courts make you take a gun safety class so you can get it back. Not sure if this is true, or rumor.
As a pirate reenactor in California I carried short Dragoon everywhere at festival and even to diner or parties at bars after (never carried powder or ball unless at a range - powder only when exhibit shooting).
One time a couple of us headed off the festival grounds for lunch at Ports O Call in San Pedro. As we passed a couple cops one asked me "Do you have a permit for that?"
I simply (politely and with a smile) explained it was a "Replica flintlock and I carry no charge nor ball"....well, he looked at me suspicious and i just smiled (never pulling it from my belt) and he then nodded and we went out marry way.
Oh, I also had a cutlass at my side, a rigger's knife tucked in my belt and a boot knife.
....twas Grand to be a pirate!
I have also often carried my blunderbuss and passed many a law enforcement, but I dont think many often knew it was real and functional.
Best advice; dont act like a jerk, always smile, and always Always be polite and cooperative.
Oh, and we all took the Safty Course even thou not required...just in case...I also took the Calif Hunting course - just good practice