Tinned 30-06 case


I have a 30-06 case that puzzles me.

It is the case on the left. It looks like an ordinary tinned 30-06 case but
there are some notable things. Basically the case is finished, except for the headstamp and the primer pocket is missing

The primer pocket isn’t cut out, but you can see a small groove on the bottom of the case where it should be. The “primer” is larger than usual and has the same size (0.24 inch) as the Berdan experimentals (case in the middle). The third case is just for comparison. If you look into the case you can also see the two holes for the berdan priming. Anybody seen this before ??

Thx for your help