I recently bought a Winchester 1897 16 ga. made in 1912. It is 28" cyl choke barrel. The barrel (takedown model) fits tight to the receiver but the mag tube does not seem to go deep enough into the receiver to properly engage the locking threads. As a result, the mag tube will spin easily when gun is assembled. It appears that the mag tube is a 12 ga. with a liner tube which protrudes slightly (unevenly). I am hesitant to fool with it and would rather have this corrected professionally. Anyone know of a good Winchester 'smith around Pittsburgh?