Theoben HE system pump/whip

[roughshooter]

£80-odd pump and HE adapter from Best Fittings.

10 or 12 strokes to pressurise the line, then do same again and check pellet speed over a chrono.

Work up in 3-4 stroke cycles, check speed before adding any more pressure.
Often find 11 fpe - ish inside 24 strokes total .
The HE's I've used were brill with a bit of a margin to the 12fpe limit.

Too much pressure and piston seals don't last long. Also the rifle is less than pleasant
to cock/shoot when over-pressured.
Don't recall ever checking actual pressure on a gauge, but as an airline could launch the low volume ram
with just a quick blast of air, I just stay safe and stick to the Slim Jim pump :-)
Have fun, great rifles.

Col