Ithaca and Fox hinge pins are straight, not tapered. When working on a gun with a tapered pin, you mill to the small diameter, then match the taper using files and scrapers. Much more complicated and time consuming. For those who asked for a pic of the fixture, here's the best I can do. Fixture is in my cabinet at the machine shop 30 miles from here. I don't have a print. I made it up some years ago while fooling on the mill. First pic shows the complete setup on the mill, with fixture clamped in the table vice, and barrel in the fixture. Also shows the outrigger I use to support the mid part of barrel during the machining. Again, you need "witness" coordinates for the barrel hook radius before doing any welding, so you can revert to the EXACT coordinates after barrel is welded and replaced in the fixture. Then you make table adjustments on the X and sometimes the Y axis for the actual off the face on that particular gun.
Second pic shows the original condition on this gun. .004" thick steel feeler gauge is a tight fit = .0035" off the face IME.
Last pic is for those who do their own soot fitting. Be sure to use a good dust mask to keep the airborne carbon out of your lungs.
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