Mike:  That is a nicely struck 'Cartouche' and your stock looks to be in really fine shape.  If you closely examine the forward tip of your stock, you will likely find a wood patch or plug (as Ned stated) that is filling the 'lightening channel' that would be exposed, when a full length stock is shortened.  A Krag built and accepted in 1903 normally would have a 1902 or 1901 style of rear sight.  A picture of your hand-guard and its relationship to the model 1892 rear sight would be interesting to see.  Also, a detail shot of your front sight and the fit of the front barrel band/bayonet lug (to wood and metal), would be interesting to see.  Any time a 26 inch barrel is mentioned on the forum it piques interest, because, there is an extremely rare (100) Krag model (Board of Ordnance and Fortifications rifle) that was experimented with in 1902.  The Bd. of Ord. & F. rifles had 26 inch barrels, but, regular Krag front sights, specially calibrated 1901 carbine sights, special stocks without the forward lightening cut, and front bands that were expertly reformed to fit a larger barrel contour.  (Your high serial number, 1903 Cartouche, and 1903 front sight, rules your rifle out.