[quote=Remington40x]Local gun shop has an almost pristine 20 gauge Superposed 28" choked IC/M. RKST gun. Serial number is 552xxV9. If I read the Browning web site correctly, this is a 1969 gun which would put it in the salt wood era. No visible sign of rusting on the exterior, but the butt plate has been replaced with a pad so there's not easy screw to remove and check for rust. Clearly shot very little as there are almost no marks on the breech face.

How likely is it that the wood on this gun is salt treated, given the age and condition?

There is simpler solution to this non-dilemma. That solution is more modern B.C. Miroku Browning Citori with choke tubes. The quality is just as good plus you get simpler forend release & choke tubes making gun compatible with all forms of non-tox shot. I read article in either Sporting Gun or Shooting Gazette by well known Englishman extolling virtues of long fixed choke barrels on old Beretta O/Us. I found this laughable I say I will take choke tubes and extra 3oz or 4oz of extra weight that comes with that feature.