An Airgun O Ring database

[LouisD]

Useful thread, thanks for sharing

[Scrinja]

[coolbananas]

My BSA Ultra MMC started leaking out of the fill end.

My old o-ring was melted and it did not look like an o-ring. The valve looked like it had a hard plastic point, but after I used goo-gone to dissolve the old o-ring, it showed I had a normal valve with an o-ring channel.

I watched XTAIR's youtube video, showing how to replace the tiny o-ring on the small brass valve inside the fill valve. But, I couldn't find what the size was and I didn't have the patience to wait for a kit from the UK.

I bought an assorted pack of o-rings and have found that the smallest one in the box worked:
A005, 2.57 X 1.78
I think this means the ID is 2.57mm and the x-section of the seal is 1.78mm.
This may not be official size, but it is working fine (2 weeks).

Hope this helps someone.