I recently received a repaired sear bar from Policeluger, the last peace in the puzzle of restoring a quite nice matching byf

I'm very happy with the result and I appreciate the help from Policeluger!
After installing the part, I decided to try the byf along with a shooter Luger.
The byf worked perfectly

But the shooter wasn't that reliable.. found out that the used shells from that pistol had a mark on it.
Is it from the extractor?? I would appreciate any thoughts about this.
Btw. I took some video while shooting, but I don't know if it's possible to upload it