If sounds like it was messed with for extra power and not set back properly. People keep messing with the regulator in HW 100 as it is an easy option to alter the power but it is the wrong option and returning the preload screw to a known position does not always guarantee return to correct pressure but uncsrewing it 1/2 to 4/4 of a turn to start with is an option. The rgulator for a full length barrel .177 should be set to around 90 bar and then the hammer preload adjusted to obtain 11.7 ft.lbs with the JSB Heavies and 11.3 f.lbs with 8.44s. You should be getting about 110 shots out of the full length cylinder at around 11.3 ft.lbs.

A.G