Thanks Dave. I was wondering that, too, as I have never seen one. Thanks also to wendell, for putting me onto 16ga.com. I will be able to get some useful info, I am sure, about my 1947 AutoLoader Sportsman 16ga. The gauge you spoke of is exactly what I figured Gander would do. It us possible those youngsters behind the counter, there, just don't have those tools and were tryin' to hose me for more money. I have options of other smithys to ask. I will try that first then go from there.
Thanks all of you for all the info.