Thanks for the update Bret. Would you consider disassembling the ejector so that any differences in ejector or ejector spring could be viewed? CZ's comment about the extractor spring is sufficient, I think. No need to remove and re peen the extractor pin.

I've noted 12:30 ejection on my 9" Bren 2MS and remedied it with an HBI gas cylinder, however ejection distance is only a few feet, 2:30 or so.

I've seen similar issues with an AR-10 type rifle. Ejection was weak and seemed to make malfunctions more common. A profound improvement in ejection was noted after the user began using a dual extractor bolt.