First would like to say that the Denver, PA show was a most enjoyable event in every respect. Thanks to Jon Cohen and NATO Dave for their hospitality and organization skills!
Was able to fill my need for an example of a “Sharpshooter” .45-80 and also found what I think is a 1902 Gatling Blank. Headstamp on the left is “R F 6 83” and the blank is unheadstamed.
Interesting that both have approx. the same 2.4" case length. Seems to be just a coincidence though? The inside primed predecessor of the 1902 Gatling blank pre-dates the “Sharpshooter” but I have not seen anything on an inside primed version of that loading.