Does anyone have any input from past experience in sleeving a chamber to a smaller gauge? The gun in question has 12 ga. chambers and a bore of .702. making a 16 ga. chamber seems a good way to keep pressures down and increase the chamber strength. Thanks, Mark

Mark II,
To answer your question-no, I don't. I do have some experience with chamber inserts, that should be the cheapest way to do what you want to do.
Mike

I had a Sterlingworth 16 ga. with ruined cambers. Two paper shells stored in it for 50 years or so had kept moisture in the chambers until it was like the surface of the moon in there. I had two choices to save the barrels, sleeve the barrels or sleeve the chambers. Since the barrels were perfect otherwise I decided to chamber sleeve them. I could have kept them at 16 but decided to go to a 20 in part for the extra metal when sleeved to 20. I had several 16's and wanted a 30" barreled 20. That was easy and what I ended up with was a over-bored 20 ga. with 30" barrels. Finding a 20 extractor and fitting it to my barrels took about half an hour to finish the job. Briley will do it for $375.00 per chamber.