1911
Manufactured 1914
1925, check the date code stamped on the barrel. Remington Society of America, Manufactured Date link has the details.
1914
Early 1920.
Probably 1925 but check the data code stamped on the barrel. Check the Remington Society of America web site manufactured date link.
1919
1920
Late 1911
The Remington model 12C slide action 22cal. was produced from 1909-1936.
1925, Remington started date code stamping in 1921 so there will be a month/year code on the barrel. You can find the details on the Remington Society of America under the Manufactured Date link.
1915
1924, see related links