They were made for shooting 22 shot shells at small clay targets or small varmints.
Routledge was an enterprising guy from an earlier era living in Monroe, Michigan. He designed the bore for 22 shooters. IIRC, he had a machine shop and did gunsmithing work. He was also an outstanding trap shooter in his day, maybe 60-70 years ago. And, he was an early airplane pilot too.
Your rifle is desireable as there weren't that many made.
I don't know what it is worth however. A collector might be able to help you on the value of it.
Martyn
