Tested various different shooting techniques from bench today and made some improvement (or so do I think).
Tightest groups were forming, when applying moderate amount of pressure against the bipod and the cheek rest. I also worked with the trigger hand and played with the trigger shoe position while doing dry fire practices. The groups were not that great (around 1.6MOA), but there seemed to be much less dispersion than before.
It looks like to me, that there’s one tighter group on each paper. With NOE the group size was 46mm for 10 shots and first 5 shots in the upper left corner are 18mm (0.6MOA). With RWS .22lr bullets there seems to be (maybe) two fliers in the lower right and without them, there’s a group of 8 shots which measure 31mm c-t-c (1.07MOA). With the fliers included, 10-shot group is 50mm.
Also did 5-shot group to 140 meters using NOE 51gr spitzers.
At the end I set up some steel plates to shoot from 120 meters, but after few shots, something happened with the valve as the gun does not fire anymore. Need to disassemble to valve tomorrow.