So its a leak which seals itself and then un-seals itself.
I think I just have to retune the level ten, but it leaks out the bolt. Not a lot, but enough to be noticeable, I thought it was a on/off O-ring but it stops when I hold the trigger, so do you think the bolt just needs to be tuned or what?
Well thats the thing, when I first air it up it doesnt leak, then I take a few shots and it starts to leak, then it seems to resolve itself and then it leaks again. Then there are times when i can shoot a full tank without any problems