I believe the forend iron and the long wood screw played a significant part in the split. The screw diameter is tapered a good bit and the top of the hole was certainly too small. Minor diameter of the screw grows from .114 to .125 and then .165 past the treads. I opened up the hole to a depth a little past the end of the screw and then bored the hole to .175 at the entrance to clear the larger diameter under the head. Then I clamped the forend snuggly and worked the screw in to reform the threads, added a little wax for lube. The forend iron would no longer fit in the groove. I had to remove a fair amount of wood so that it would fit. Maybe .010 or so. Lot of shrinkage over 113 years I guess.
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