RW is Remington Works, not part of the serial no. 1912.
your Remington rand was made in 1917.
Early 1911
Manufactured 1909
Get the date code stamp off the left side of the barrel and look it up on the manufactured link on the Remington Society of America.
I posted a link (related links) for Remington on their archive page to bolt action rifles, you might be able to identify it there.
1923, will be date code stamped see related links.
1929 if it has the original barrel it will be date code stamped. Check the manufactured date link on the Remington Society of America for details.
I just don't think that's a Remington made 1911A1 Serial no, are you sure it's no mixed parts? May be Colt, 1924................
Model 581.
Probably VERY early 1939. Best to check the barrel codes, look up the details on the manufacturing date on the Remington Society of America.
Are you sure it's an auto and not a pump action, it sounds like the predecessor to the Remington Model 10.
1955