Here are some lousy photos of another Mannlicher – Schoenauer M1900 Stutzen just like your's: Same stock shape with round pistol grip. Same peculiar front sight base. Same receiver ring inscription.

One feature distinguishing the M1900 from the M1903: The M1900s had a flat spring inlaid into the left side of the cocking piece, retaining the firing pin nut. The M1903 omitted this unnecessary spring, replacing it with a small tab on the bottom of the nut..

Early M1900s had the cartridge release button on the outside of the action rail, between metal and wood. Later? ones, like your's aqnd the one shown above , had it inside the action rail just like all other M-Schs from the 1903 on.

Be careful on disassembling a M1900 bolt(I learned it the hard way): Like with the later M-Schs, you remove the bolt from the action and uncock it. You push the safety flag forward a bit an swing it to the right, safe position. Now you unscrew the striker nut a quarter turn. On the later M-Schs the bolt head stays captive and has to be turned to remove it, striker and main spring. Not so on the M1900: As soon as you remove the striker nut, the mainspring will eject itself, the striker, bolt head, extractor and ejector out of the bolt body. These parts usually fly into the darkest corners of your room, after shattering a precious Ming China object. Especially the tiny extractor likes to disappear forever.