Quote Originally Posted by Benelli B76 View Post
PTFE does not need explaining to the guns but to people. PTFE can be cut with a knife. It is usually white in colour and is malleable that is why it is used for flange seals etc because it adapts to shape. A lot of people look at a synthetic seal in an air rifle and call it PTFE when it is actually polyurethane because they do not know about polymers. You can use it for piston seals but it will not give a good seal eventually, that is why airgun manufacturers do not use it. I repair airguns every day and never see it except on old Webley pistols, and it is used on the capsule seal for the Tanfoglio Witness pistol which is why they need to be changed after squashing out of shape.

Baz
Fair comment Baz. But I'm just wondering why these seals have performed flawlessly over the years for me? Not just one or two but all of them with exception of those mentioned above and for I don't know how many cycles?
Have I just been lucky then? Ive stripped a few to check and there has been nothing adverse noted?
As I say the moment any give me trouble I will strip them out. But I don't see the need when they perform so well?
Perhaps design also has something to do with it? I know my old mk 1 Vulcan uses a ptfe seal and is performing well after all these years.
I have the luxury of two identical Diana's T01s (albeit different calibres) and will definitely go the oem seal route next time around and compare.
Dave