I don't beleive your ejection problem is gas related as you have the same results with hand cycling.
My thoughts are a mis shaped ejector, factory weak ejector spring and or both. You can always disassemble the carrier to inspect for maching burs in the ejector pocket as well.
The ejection port does look tight, but you would have case damage if it was hitting. Also, hand cycling would make this very noticeable.
I think it is ejector/bolt related solely. Have you inspected the rim of the casing for odd markings?
My thoughts are a mis shaped ejector, factory weak ejector spring and or both. You can always disassemble the carrier to inspect for maching burs in the ejector pocket as well.
The ejection port does look tight, but you would have case damage if it was hitting. Also, hand cycling would make this very noticeable.
I think it is ejector/bolt related solely. Have you inspected the rim of the casing for odd markings?