They started building NM rifles in 1919. IIRC both they and RIA built NM rifles that year. Therefore, there were NM rifles manufactured in 1920. I have 1919 NM, Springfield # 1,092,290.

In looking at the rifle above, the receiver, rear sight, follower and bolt all look NM; I can't really tell about the left "raceway". It should be polished, as well.

IIRC, this was before either the barrels were marked with a Star Gauge "turtle" on the crown or the bolt was etched with the serial number.