I know this has been asked before but I just want to clarify, I’ll be flying to Santa Barbara next week with my son (13yo) and picking up a car to drive back to Tx, my question is can I fly to Ca with a gun? I’ll bring either a g43 or a colt 1911 because those are the only guns I have under 10 rounds, I’d be taking an Uber from the airport to the hotel and the an Uber from the hotel to the place where I’m picking up the car ( Santa Barbara police department ) from there we will be driving back to Texas , is this even posible or am I crazy and should just forget about the gun? I just don’t want to drive halfway across the country unarmed with my kid.

Thank you for your help.

You can fly to California with a gun.  I'll assume you haven't done something creative (like a threaded barrel) that might make the it an assault weapon.  You're right - 10 round magazine limit would apply.  The flight container requirements are stricter than the container requirements for transporting a hand gun in California.  

I would suggest coming up with some way to not need to take the gun to the police department.    I don't know what if any security issues there are, if you need to go "in" to do paperwork and maybe  they do bag checks, etc.  To avoid complications or surprises.  Or maybe consider calling them and discussing it in advance.  (Much like they want you to do if surrendering a firearm. They don't want to be surprised by someone walking in the front door with a firearm.).  

Otherwise, transporting an unloaded handgun in a locked container is fairly straightforward and discussed in lots of threads.  Note that a police officer is allowed to inspect a firearm in public (public place or in a vehicle, etc.) to see if it's loaded in violation of carrying a loaded firearm laws.   Once you are driving, I'd suggest keeping the container out of sight anyways.  No need to make anyone curious.

I'd suggest timing the pick-up so that it's complete before you check out of the hotel.  It'll make that aspect much easier.

You can have a firearm unloaded and in a locked container in your vehicle without restriction.  Mags can be loaded. Mags and ammo can be in the same container, or be unlocked, on your person, etc.  The container can be in the main compartment with you and accessible.  Can't use the center console or the glove compartment, although a lock box fixed to the inside of the center console is apparently okay now.

As was mentioned, California has a 4th Amendment "exception" for guns to see if they are unloaded.  I, too, would suggest not having the container be visible unless it's not something that looks like a gun case (like a locked compartment in a backpack or something).  I would not tell an officer about it.  California is not a duty to inform State.  No good can come from that, even if nothing bad happens.

For travel outside of a vehicle, you can't just carry the gun this way.  There are destination requirements, such that you can only carry it unloaded in a locked container going immediately to and from your home, other private property where you have a right to be, the range, an area where shooting outdoors is legal, a shooting competition, hunting, an FFL, from car to indoors and vice versa, etc.  

Your hotel is treated like your residence, so you can have it loaded, carry it however you want, etc. inside of the hotel room.

There are some exceptions to the above, but they aren't going to apply to you on this trip.

Make sure your guns do not have threaded barrels (that makes them assault weapons).