Hi Greg, I'm from the North Shore of MA. Revere to be exact. Now I read your question and my thoughts are that if your looking for colonial finds you shouldn't be looking for beaches, you should be looking inland woods, feilds, lots, etc... There is a chance to find something good on a beach but not what your looking for, Although they all say TREASURE IS WHERE YOU FIND IT! Well anyways that's just my opinion.
Good Luck
HH
Paul O