At that age, he's just testing boundaries. If you grab him up, clamp your fingers on his little beak for a few seconds and carry him around, that usually breaks the young ones because they are not dealing with raging hormones yet. Even my sweet, calm, mama-loving Isaac did the biting thing when he was about 13 weeks old. Doing that to him twice broke him of that bad habit and he hasn't done it since. Had another BR cockerel who did the biting thing at 8 weeks and that holding the beak and carrying him around broke him in two tries.
The main difference is the age, remember. I completely think that most that are really not destined to become human aggressive can be easily broken of it when very young, before the hormones kick in and before they are mating the ladies.