The picture Pivi posted must be of the cartridge based on the .44 Magnum case, not the true .41AE based on the .41 Magnum case. The round in the picture is clearly semi-rimmed, like the early browning Cartridges (.25, .32, .38 Auto, etc.), and not rebated rim as in the .41 AE cartridge. This squares perfectly with the dimensions supplied by Pete DeCoux about this cartridge (Rim: .475"; head (base) .453").
It is a great prototype cartridge due to its provenance! It evidently went nowhere, because I know of no production cartridge that would begin to correspond to this round. If some one can think of one, please post the information.
Pete and Pivi - thanks for the picture. This is totally a new one on me. Pete, you shoud give this cartridge a name more descriptive of its dimensions. With the principals involved now gone, you are the best qualified to attach a descriptive name to this cartridge. (.44 AE SR???)