alot of them are like that, and almost all young Cals do what you described. As the snake ages, and I'm talking like up to a year, not in a week or two, it will lose the striking behavior but may or may not lose the tail rattling. I have had adult females that always rattle when the cage is opened. One female still musked every time. Regular handling can help, but no matter what, realize that Cal kings tend to be defensive at first.