Over the weekend I acquired a RWS Diana Model 6 Recoilless Air Pistol. From what I can find online this is the "Original Model 6" manufactured in the 1960s. It did not have the box but the seller claimed it is unfired and based on condition this is probably true.

Everything seems functional except it does not propel a pellet. I'm guessing the piston seals need to be replaced. Has anyone here worked on a double piston air pistol that can offer some insight or things to be aware of during disassembly/reassembly?

diana6.jpg
Google file photo