It's doing what nature designed it to do. Handling a snake a couple times a day is putting it under an extreme amount of undue stress. In nature an 18" Cal King is food for everything
and it's only defence is to musk and strike. I only handle my small kings about once a week, when I'm feeding and cleaning their shoeboxes. Most kings will calm down with age, but I still wouldn't handle them daily. It has been said on this forum before, snakes are not "pets" in the normal sence of the word. They are NOT domesticated animals, no matter how much we try to fool ourselves that they are. They will always retain their natural instincts to eat, breed, and defend themselves.
Sound like you have a nice normal healthy acting Cal King.
-Phil