Converting the Webley Senior from a piston ring to a leather seal?

[eyebull]

Hi

I am very interested by this thread as I will have to refurb my junior. Junior has a leather piston seal but the breech seal is my main concern.

For my curiosity, I have a few questions for you guys:

What does 'PB ring' stands for?
What is the material of this ring?
Beryllium copper?

Many thanks

'Phosphor Bronze', answers both questions I think

I must admit to always being very keen on the concept of the PB piston seal. As I understand it the reason it was not used in future Webleys was due to cost, rather than leather seals being an improvement.
IIRC the FWB65 uses a PB piston ring, and that was not a 'cheap', or half-arsed, pistol.

They are meant to have an extremely long shelf life, I seem to recall figures like a half million, or a million shot cycles bandied about, particularly with reference to the FWB65. For that reason I'd be inclined to keep it in situ...