Winchester did rivet the heat shield to the adaptor. They then filed the rivets down. If you look at a WWI 1897 heat shield you can't see the rivets on an original condition gun. On the WWII Model 97 and Model 12 trench guns you can see the rivets. They apparently did not take the time and effort to file and smooth the rivets down like they did on the WWI guns. I could show you photos of the difference, but I don't know how to post photos on this webste.