Steve, In Brophy's book "L.C. Smith Shotguns", there is a page that gives all the chamber sizes, and yes they are all tapered. The dimension of .797 is at the end where 2.750 is. The opening is .811. From the beginning L.C. Smiths were 2 3/4" chambers in 12 ga., but never say never, if you wanted it shorter they would do it. "Anything within reason".