chopperlump,
Thanks for the info. If it didn't have 2" chambers, it would not be what I am searching for. By the way, I had no intention of purchasing. I don't need to own it.
Miller,
Thanks as always. '27 would be the outer edge of activity. Ithaca produced a sxs 410 in the same year. But your information reinforces my belief about the Gabriel book. I can confirm single barrel 410's as early as 1913, by Stevens.
I have tracked down the origin of the 44XL by the way. It had been in use for nearly 25 years before it was ever chambered in a smooth bore. It was a common loading for the Winchester 1873. This was in addition to the 44-40 chambered guns that were out there.
Pete