Hi All,

At my wits end with my old Ultra. Its an early .117 MMC single shot that is leaking past the knock open firing valve. I have re-sealed the whole gun while its been apart and put in a brand new knock open valve and stem seal but it continues to leak when filled.

It has an after market Huma reg fitted.

When the old valve was removed the face was slightly rounded but the new is a square edge. I am not sure if the slight bevel was due to wear? Looking inside the valve body the mating surface when the valve seats looks conical. Should the replacement valve be beveled slightly?

Its been cleaned out many, many times and there doesn't seem to be an dirt etc stopping a seal.

I have pretty much run out of ideas..Anyone able to offer any help or advice?....I'm stumped!!

Cheers