I’m not sure exactly what you are after. The extractor on a Darne is one piece, both unfired shells are lifted out of the breech perhaps 1/4” when the breech is open-there is no left and right spring, there is just one, rather stout spring that drives the one piece extractor.
The ejectors are just hooks that catch the rim of the shells, pulling them out until they reach a cut in the action flat, that allows them to release the rim. There is no spring in that system.
I’m out, but, either Geoffrey Gournet or JJ would be worth contacting.
Best,
Ted
