Living in Los Angeles County, in the great communist state of California, You better watch out. Although Air Rifles are not Fire Arms, the State, County and most Cities have rules like the following:
In California, not just anyone can buy a BB gun. In fact, it’s prohibited to sell a BB gun to anyone under the age of 18 or provide one to minors without their parents’ permission. In addition, this sort of weapon is not permitted on the grounds of any public or private school without permission. If you own a gun like this, you are not allowed to draw it or use it in a threatening manner in a public place. Additionally, the state prohibits you from drawing your weapon in a public place. In any area like a government building or public transit facility that specifically states BB guns are not permitted, it is a violation of California law to possess one.
There is a law which allows someone to carry a rifle on Public Land, but I would call the sheriff in the area a couple different times to double check the answers given a couple times. You can also call the Game Warden in the area and ask them specifically about the area you will be in and have them site the State Code, COPY THAT DOWN, PRINT IT AND CARRY IT WITH YOU. I'd also have a CA. Hunting Lisc just to cover your backside a little better.
Smitty