tahunua001 brought up a good point regarding service rifles, that being parts interchangeable, that is a critical aspect when you have to deal with logistics during war time.
Americans always see to insist on parts interchangeability, some times causing production delays, such with trying to standardize the M1917 while also trying to produce enough for the troops who were on the ships heading to Europe.
Some times that creates sloppy but reliable guns which also can still be quite accurate as in the case of the M1911, M1917, 1903s and on to our present M9 and M16 series.
As to accuracy I'm of the opinion there has never been a bolt action military rifle as accurate as the M1903/M1903a3. But saying that you can't compare the the 220 gr. RN bullet for the Krag and or the pre-1906 M1903 ammo with the M1 ball with the 172 grn bolt tail sp bullets, or even the M2 152 gr bullet.
It's strange that with all the great post 1903 Springfield actions out there the Army still uses the Mann Device built on 1903 Springfield actions, to test todays 308 ammo.
In "The Book of the Garand" by Maj Gen Julian Hatcher, Hatcher relays informant ion about Post WWII rifle test, competition shooting, of the M1903 and the M1 Garand, just about in every event the Springfield out shot the M-1.
This is not to say the Springfield is a better "battle rifle" then the Garand, but does indicate the Springfield is not lacking in the accuracy department, even considering the better sights on the Garand compared to the Springfield, even the M1903a3, which has 4 MOA windage adjustments compared to the Garands 1 MOA windage adjustments.
CPT USAR Ret
USAMU Sniper School Oct '78
Distinguished Rifle Badge 1071