SAGRAM NOMICAN AIYER
Yes.   If the scalp hair was in situ and if the person had a thick mob of hair, it is not unknown for a person to miss a gunshot wound unless you tease the hair apart and look at the injury.  Quite often this is why, in fact it is mandatory for us to shave the scalp when we suspect a gunshot wound, we shave the scalp to get a clear vision.
	However, on opening the skull itself, the calvarium and if you examine the calvarium, you would notice if there was a bullet wound, the bone would have been fractured, one would note that fracture.