Am I missing something with this ram?

[autococker04]

I’m trying to rebuild this ram, it’s dumping air out the back (toward the gun body). I sold off most of my cocker stuff so I don’t have anything to compare to, but I swear there’s supposed to be a tiny oring that the ram shaft slides through. But on this ram, it feels and looks smooth on the inside both where the barb is and where the ram screws into the gun.

So if anyone knows what kind of ram is this, and what am Im missing, help would be greatly appreciated.

[superman]

Here you go.

https://www.youtube.com/watch?v=e7qJLyk5EZ8

[autococker04]

Ahh, I just watched the exact same guy do an STO ram and should have just kept searching for ram types. This is exactly it, I don’t think mine even has that big seal in there.