It seems to me that there is an unusual amount of wear to the finish at the edge of your ejection port. My SA has at least as many rounds through it as yours does and shows nothing like that kind of erosion to the finish.
As I'm sure you know, those dings are caused by the case leaving the port. The case head hits the ejector as it travels rearward after ignition and is thrown to the right. It starts to spin as it travels and the case mouth hits the side of the action as it spins off out to the right. I suspect those deep dents in your cases are the result of the cases being slammed harder than normal into the botom rear edge of the port. This might result in the case momentum being redirected and the case rebounding back into the port instead of being thrown clear. The second ding near the base is the one that intrigues me. It's not normal to have two dings in the brass. This second ding suggests to me that the case is hitting something it's not supposed to, something that is causing it to return into the action. Maybe the top edge of the port?
Could harder than normal ejection cause the case to hit the back edge of the port harder and then bounce upwards contacting the top of the port and flip back inwards instead of continuing out right?
Did the Shooting Edge's smith check the diameter of the gas port on the barrel against spec? Maybe the port os too large and is putting too much gas back onto the piston.
Virtually every other moving part has been swapped out. What's left are the most likely candidates. Barrel gas port dimension and out of spec ejector are the two possibilities that spring to mind.
As I'm sure you know, those dings are caused by the case leaving the port. The case head hits the ejector as it travels rearward after ignition and is thrown to the right. It starts to spin as it travels and the case mouth hits the side of the action as it spins off out to the right. I suspect those deep dents in your cases are the result of the cases being slammed harder than normal into the botom rear edge of the port. This might result in the case momentum being redirected and the case rebounding back into the port instead of being thrown clear. The second ding near the base is the one that intrigues me. It's not normal to have two dings in the brass. This second ding suggests to me that the case is hitting something it's not supposed to, something that is causing it to return into the action. Maybe the top edge of the port?
Could harder than normal ejection cause the case to hit the back edge of the port harder and then bounce upwards contacting the top of the port and flip back inwards instead of continuing out right?
Did the Shooting Edge's smith check the diameter of the gas port on the barrel against spec? Maybe the port os too large and is putting too much gas back onto the piston.
Virtually every other moving part has been swapped out. What's left are the most likely candidates. Barrel gas port dimension and out of spec ejector are the two possibilities that spring to mind.




















































