I would never let my pup bite me to the point where I'm bleeding. If you're allowing that then of course he thinks biting that hard is acceptable behavior.
I would smack him on the snout with a firm no! when he bites hard. Then I would redirect to a toy. If he engages the toy then praise the heck out of him. He has to know biting you makes you mad and playing with the toy makes you happy. If he doesn't engage the toy and keeps on biting you then time out.
My pup at that age had to go "jail" a bunch too. Key is to be consistent and it will pass.