I have a yearling corn that has pretty much the exact same attitude.
I've only had her for about a month, and I gave her about two weeks and two meals to settle in to her new home. She bites me every time I try to get her out, unless I can get her moving and scoop her from the middle of her body. She also will occasionally turn and bite me while handling if I move my hand up to support her somewhere within a mile of her head.
She's at the point where she draws blood occasionally, and she's the first snake I've ever owned that's actually tagged me at all.
You say yours eventually calms down after some time out? That seems like he will eventually get better. Corndog never really calms down, she just flails when you support her anywhere within 6 inches of her head and if she ever sits still for a few seconds, then when you move at all she bites you.
Moral of the story: it could be worse. It will definitely get better. Just handle him often. At least that's what I'm going to do.
Re: Corn Handling Question.
Out of my 21 snakes, most are corns. Baby corns tend to be very active and move constantly. If yours is biting, he is most likely biting out of fear, not aggression. Since he is smaller now, handle him now, a lot, every day that you can (allowing, of course, for digesting time). He will get used to it, and realize you are nothing to fear. He may also get better as he gets older. Several of mine went through nippy teenage phases and then grew out of it.
Re: Corn Handling Question.
You could try to either take him out for 10-15 minutes everyday, or maybe 1/2 hour every 2 to 3 days. Gradually build up from where you are. As long as he is eating good, I would not really worry about holding him too much. If he stops eating, then back off.