Well HUMA Reg took care of my problem mostly still have a POI shift but only about a 1/4 of inch on first shot after sitting all night. My consistency from shot to shot through Chrono is only 12 fps so happy with the change out.. Have HUMA set at 125 bar loves the .25 JSB HADES one ragged hole at 50 yards. Other added item was a superior slug liner barrel in 600mm can shoot slugs and also 25.39 JSB with very little change in scope setting.