there is a little set screw on the striker/hammer that tightens against the adjustment screw. If that screw is not snug, it's possible that the power setting my change if the adjustment screw turns freely enough (some screws may fit more snugly in the threads; I've seen this in a replacement hammer). Anyway, put something in between these two screws so you don't have metal-to-metal contact or you'll have a bear of a time trying to make adjustments. I use a bit of hard plastic that protects the threads of the adjustment screw form being boogered up by the flat bottom of the set screw. I can snug things up enough to prevent unintended backing-off of any adjustment I make.
JK's Airgun Forums, moderators, and administrators are not responsible for any problems that may occur from reading or using content posted on this forum, as they are the exclusive responsibility of two parties: the person who posted it and the person who acted on said posted information.Use of our forums by people under 18 years old is allowed only with legal guardian(s) present..