Ovidio-- It sounds like the Winchester may be a late production rifle from the barrel date. The first 10,000 or so Winchesters had a compatibility problem and General Pershing, the US AEF commander requested that no Winchesters be sent to Europe due to compatibility issues. It seems that Winchester jumped the gun and started production of the M1917 without using approved blueprints from the US Army Ordnance Department. Compatibility was achieved by January 1918 but the damage was done. The general idea was that each US soldier in the National Army (non- Regular & National Guard Division Troops) would have two M1917 rifles available to him. One that he would personally use and an operational readiness float in event his rifle should be damaged, lost or destroyed. The Winchester M1917 usually bring a 30% added premium here in the US. I recently saw a Rebuilt WWII Winchester with a rough bore sale for $900.00 US.
Enjoy your new rifle.