The A works well again, although it has a slow leak (valve with 6 pumps in was empty the next morning). I have decided that this is not relevant; for shooting, the leak is not fast enough to cause inconsistency. I think it comes from the threads of the two valve halves. I used one layer of 1 mm ptfe tape. A tight fit, but perhaps I should have used a second layer. It is also possible that the inlet valve still leaks a bit, but I cannot hear it.

After adjusting the pump rod (increasing length), so that the pump arm cams over, I am now getting 699 ft/s with 13.73 gr JSB, at 8 pumps. That is quite a bit more than before. Luckily I live in Holland (no power restrictions here).

Cheers

Finding the right length of the pump rod; adjust, test, adjust, test. Until it cams over, but not too much. I used a pin punch instead of the original pin, for ease