Seems, to me, the pull weight adjuster was too far out to begin with. The symptom you describe is typical.
Remove screw to check spring is not buckled. Refit spring carefully to avoid fouling in casing. Screw adjuster in till spring resistance is felt.
Keep checking operation with quarter turns on adjuster till satisfactory.
With action out of stock trigger can be cocked, without latching piston, by pushing main sear with punch etc