I took my original adapter and the homemade heat shield to the local shop here. He looked it over and suggested that heads of the steel rivets were probably inserted from inside and peened over on top of the adapter. My thoughts are that original examples look a little too uniform to be peened over but inserted from the outside top of the adapter. What he said does seem to make sense too though.... I can't really tell for certain.
Anyway he didn't didn't have any steel rivets and couldn't attach it so I need to find some 5/64" steel rivets somewhere and if so I think I may be able to eventually attach it myself.

I'm curious if the original trench gun barrels were slightly thicker to compensate for the grooves for the adapter screws.

Dick

---------- Post added at 01:04 PM ---------- Previous post was at 12:57 PM ----------
Quote Originally Posted by browningautorifleicon View Post
The sporting barrels are completely different. Thinner and tapered. The riot and trench are almost a straight taper and thick.
Thank Jim...I forgot about that - do you know if the grooves for the adapter screws compromise the barrel strength on a sporting barrel as long they're not over done?