The "Routledge" bore was developed by trapshooter Fred Routledge in 1938. The idea was to allow indoor skeet and trap shooting at tiny (2-5/8" dia)clay targets named "Moskeeto". The targets were thrown 75 ft. The Routledge bore would pattern about 80% (92 - #12 pellets) at 35 ft. Winchester made the Mod 61 with the Routledge bore until about 1940 when they designed their own counter bored barrel. It was very similar to the Routledge, but differed in the length of the counter bore and bore dia.
Simmons installed vent ribs on a few Mod 61's making them look a lot like a miniature Mod. 12.
OB
