You can open carry in a national park or national forest provided you adhere to state rules regarding the weapon you have.
In our state I can open carry anything legal from an AK to a .357 to a 12 ga. I don’t, but I do legally carry concealed.
If I went to Kalifornia I would be arrested for the possession of anything.
A off subject tidbit, I was in a farm store today buying ammo on a 15% off sale. A Canadian was behind me at the cash register and said up there they need a license just to buy ammo. I asked this guy if he liked Justin, and his reply was how much this jerk looks like Castro.