Even a wild caught corn usually is pretty docile. You did not say how long you have had this snake. However, I don't think this is a case of him just settling in for a few days as he probably doesn't even know he's in a new environment since he's still in his old tank. If he is being aggressive and not just defensive, he may have actually been abused. If that's the case, you will have a long road in rehabilitating him
I agree with the vet visit recommendation. If he turns out to be healthy, then you can start socializing him. I would take it slow though. Rather than yank him out of his viv to feed him, I would put a smaller sterilite tub in his viv with him and wait for him to crawl in with the prey. Once he's done that you can put the lid on the tub, remove it from the viv, and clean his viv. Kind of a modified "hot" handling. Since he's used to eating in his viv, he should take to this routine.
Once he's used to eating in the sterilite tub and being handling via the tub. He will become less aggressive/defensive and you can try handling him. However if he continues to hate being handled, I would just treat him as a hot (as described above) and enjoy your new acquisition from afar.
I also would reassure you that the worst corn bite isn't any worse than an average cat scratch. I admit I've only experienced five or six snake bites in my lifetime and they have been from medium size snakes less than four feet long. So if any of you out there feel that I should be advocating more caution, please jump in.
I just feel that even among ourselves we still have a snake phobia...a primal fear of being bitten. I used to jump back six feet when my three foot king would strike at me. I was 30 years old before I reconciled what I knew with what I felt. I'm 57 now and when one of my snakes tries to bite me, I feel like such a bully, forcing my 100,000 grams on this 300 gram snake.
Sorry for the wandering reply, but I feel so bad for both the snake and the new owner when handling ends up being so stressful. I'm sure you will be able to work it out with the new guy.