Is there any reason the precision trimming of a doubleguns chokes would not be a practical alternative to reboring? The taper would be shortened ,but the end restriction could be opened slightly and accurately by substituting a milling machine or percision grinder for the hacksaw. Perhaps this is done?
I had this done to a Model 100 SKB. Wrote to the Ithaca factory and got the engineers to calculate how much I would have to cut to get the desired choking. It was less than 2 inches to give me just a little constriction in the right barrel and tight improved cyl in the left. The gun is long gone now as it started doubling on me and I traded it.
