What inherited firearms?
Since you were willed the firearms, by name, it is an easier process. Now banned (in MD) firearms purchased by your uncle after 10/1/2013 gets a little trickier and I can't answer that.
I would hire the services of a MD attorney well versed in 2A law. Brit Stouffer and Ed Hershon are spoken of very highly.
Maryland State Police approved the transfer today or really did not disapprove of the transfer.