Nanjim said:Rockhunter62,
That case might be a 22 Hornet
Sorry mate, no. "The one in the middle is rimless and a little larger than the .22 long rifle case and hollow." I would believe that the internal diameter would be about quarter of an inch/6mm. I can put the .22 case inside the tube.
I think that Megsy might be on the right track.
Cheers
Doug