One way for Mosins to miss the upgrades would be for it to have been removed from Russian hands. The Russo-Japanese war took place mostly in what was Manchuria and the Russians were defeated in a number of ground battles by the better trained and led Japanese. During or at the end of the war, this Sestroryetsk was captured by the Japanese forces. The stamp on the buttstock is translated "Imperial Japanese Ryuto (Liaotung) Government Supply Depot Proof." It retains the old style rear sight, magazine and front band swivels and has not had a crossbolt added. I have no idea what happened to it after it left the Liaotung (Liaodong) peninsula until I bought it from a seller in Georgia in 2008.
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It is easy to see the lack of a crossbolt, the early rear sight, and the magazine swivel in this photo.
The metal shows some pitting and the arsenal marks are not heavily struck.
The bolt does not match the rifle but the cocking know matches the bolt.
The magazine does not match either. The marks near the swivel indicate the magazine was made at the Chatellerault arsenal.
There is no serial on the butt plate. There is an old nail in the bottom screw hole. I just left it there.
Last images are a trigger detail and front swivel detail.
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