Kevin has the scoop, from the Maryland Shooters forum. It's amazing people still wonder why we react the way we do to calls for licensing and registration. The MSP came to his door in the middle of the night armed in full tactical gear all because their registry flagged his purchase of "large amounts" of ammunition. The gun owner had done nothing even remotely illegal and yet there's a SWAT team in his house in the middle of the night. That should scare the hell out of people, and not just gun owners.
I have a thousand rounds coming tomorrow. Good thing I don't live in Maryland.