How old is it?
Stadt’s “Winchester Shotguns and Shotshells” says Winchester loaded them from 1916 to 1949. Winchester introduced their Model 36 single shot 9mm shot gun in 1926.
I’ve been told the red paper shells were smokeless powder, Blue were black powder and green were Lessmok. I don’t remember ever seeing any boxes for the Lesmok loads. There are also purple, tan and yellow cases.
Winchester also made a proof load with a tinned base and blue paper. And dummies also exist with a small hole in the center of the base / head. Plus they also loaded ball rounds and single charge shot loads.
Just to give you more to look for.