1909 - 1936
After 1920 they are date code stamped or a serial I can date it with.
If it says model 12 on it, it's probably date code stamped see related link for details.
That is the complete. Model 12A It's the basic model.
Remington Works - 1914 (late)
Made 1915
1912
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1919
1919
1912
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1918
Early 1920