I have the same gun, over 30 years old, and after throating and releaving the ejection port, I have never had a problem with any ammo. Tell us more about the load, reload, case, etc. describe the marks from the pin strike, as I am curious.
Not much to tell. It was store bought RP, 45acp. I donot remember the weight of the slug, but nothing out of the normal.
I loaded it, pulled the trigger, it went bang, left a sad looking group. I swept the area before shooting. I recovered 100 cases out of 100 fired. so I doubt that they are someone else's cases. And only two of them have the double marks.
The markes are side-by-side and overlap each other by abou 1/4 of the diameter. They both seem to be the same depth.
I just can't figure what would do that on 2 out of 100.