Webley Axsor Magazine Mechanism Question

[Chainsaw Rebuild]

Hello! I’m rebuilding a Webley Axsor air rifle and I’m nearly finished… it’s had a thorough clean, new seals, and pellets removed from the barrel.

The gun came to me in bits, and I think I might be missing a something because I can’t get the mechanism that lets the bolt action rotate the magazine back together.

There are diagrams online but I can’t see what I’m missing! Has anyone got experience with one of these?