I don't have a lathe or access to one. I needed to cut a 'step' at the muzzle of the 21" barrel for the 1903 front-sight.

I decided, I would hand file the step. I made a 'barrel holder' by nailing two small pieces of thin plywood to the ends of a stub of 2"X 2". I cut a "V" notch in the plywood at each end.
I put four layers of masking-tape around the barrel to serve as a guide and protect the full diameter barrel 'shoulder'.

By intermittently rotating the barrel with my left hand as I filed with my right, I was able to create a neat 'step'. I varied using coarse and fine files. I polished out file marks as I went along using strips of emery cloth (using both hands, like a shoeshine boy).

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