How to stop my dog from nipping/ biting?

So I just adopted a 7 month old hound/lab/pit mix from my local shelter. Hes a great dog! But hes a little bossy and hes getting nippy and biting. When he plays with the other dog and i pull him a way he nips at my arm, when he gets all pumped up he runs and goes for my legs. One time when we were playing he jumped up and snapped at my face. When i disipliced him the other day he layed down that jumped to bite my finger. Hes snapped at my face a few times. Ive tried spraying him with water (he gets bolder and it doesnt bother him), ive said no, ive held his mouth, his tounge, ive held him down (he gets worse and when i let him up he snaps at me again!!) ive tapped his nose. He just has gotten worse. Help!! I dont want a puppy whoses going to bite!!