Thanks for the replys! I guess I'm a bit slow, but I don't see how one could make chamber sleeves to fit a 10 gauge with 2 5/8" chambers unless one went to 2 1/2" 12's. I'm very familar with the concept odf inserts as I shoot skeet with full length tube sets. I've fit a set of tubes to another gun with tighter chambers and it is imparative the fit be good or the tube can and will split - especially the 20 gauge tubes. If I did make inserts, I'd want to soft solder them in and make a new extractor so the shells would lift out correctly. But doing so would alter the gun more than I care to do and if I want to shoot a 12 gauge I can just get one out of the safe!
I've made some more calls and decided to use 2 5/8" hulls and cut the powder charge back and chronagraph the loads and work back up to around 1150 fps using a slower powder such as 7625 and 1 or 1 1/8 oz of shot. Am also going to take Jerry up on his kind offer to send me some data. Thanks again, Don Hansen.
