I had a cut-down Krag barrel that someone dovetailed a horrible front-sight on.

I enlarged the opening, of a 1903A3 front-sight band, to fit on the barrel. I improvised a 'key' from aluminum by Filing it to shape.

It fit in the dovetail and provided a 'key' for the sight-band. I notched the top of the Key to accept the 1903A3 sight's lower cross-pin.

Aluminum works good for this purpose, since it is easily shaped and conforms.

Only the 'Key' ends show and can be blackened with a felt-tipped marker.

(Admittedly, a 1903 front-sight looks nicer. Krag barrels have usually been 'stepped' by reducing diameter, to fit a 1903 sight. If there is a 'flat' in the sight area of the barrel you are working on, you can make a simple 'key' to size from aluminum).

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