'Battis32' - You will need to 'step' your barrel, (reduce the diameter of the muzzle end of the barrel), for the 1903 'banded-base' to fit.

Another possibility is increasing the inside diameter of the banded-base with a 'hone' like device, until it fits. (I have done this, but, it takes forever).

I have successfully anchored a couple of 1903 sight bases on barrels by drilling a shallow hole, where the spline would be, and 'gooping' some "JB Weld" glue in the 'spline-slot' of the 'banded-base'. This cleans up easy and is invisible.

With a bit of heat, base can be removed, if necessary, at a future date.

p.s. - If you check the KCA heading "Other Firearms", there is a thread I started, ('1903 project & Khyber Pass gunsmithing'), that describes a similar install.

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