Fulton Armory Barrel

[INLAND44]

Yes, it would be more involved if you plan to accommodate a standard front sight, including milling the keyway into the top of the barrel. I would call ADCO about it. Or, you could leave it short and SBR it. Probably cost about the same either way.

[Claven2]

FWIW, you could also have your smith bore out the slide area and press in an 18" barrel, solder them together and add a through pin just behind the gas block for good measure. Re-chamber, and you have a proper looking barrel. Or alternately, just buy a new Criterion.

[browningautorifle]

Although it's a bit harder to do, Claven has a point. They did re-furbish demilled carbine barrels like this sometime in the pot war years...I had one here for a bit. Two groove, ex 1903A3 barrel that had been re-machined and chambered. It looked and functioned perfect.