The rim won't stop the case. These have a deep recession for the rim, probably double the normal thickness. The rim doesn't quite fit inside so would have to be trimed slightly. I could probably force it in but I don't want to do that. So the headspacing would have to be on the top of the cartridge. You can't see it in the photos but the cylinders are not straight walled. They have a step to where the bullet enters.
The link is mostly for the 73 French revolvers which use a different cartridge. They mention a couple of others including the 12mm Perrin but this is an 11mm thick rimmed Perrin.
Below is what I'm proposing. It is NOT to scale:
https://www.milsurps.com/images/impo.../kEbxA6n-1.jpg
