First a plug. Our book has ten pages on only the Smooth Bore Rem 22s including a lot of info on Fred Routledge. See home page for ordering details.
The Routledge bore originated in Fred's workshop as a configuration to improve patterning in the SB rifles. It increases the SB to .40" for approximately 1/2 of the barrel length.
The 514 Routledge came in two barrel lengths; 19 1/2" & 24 3/4'. No production #s have been found but they are not that hard to find.
Many of the other SB rifles have been called "Routledge" because of the .40 cal muzzle.