if the longer screw is now screwed all the way in , then you have an issue with the trigger . IE a casting burr or something eather on the trigger bars or on the nose of the main spring causing more pressure to be applied on the rear trigger . there is only about 3/32 diffrence between the old screw and the new one lyman uses. having the screw tured all the way in means that the front trigger notch is at its steepest angle and least amount of engagment .. again with tht longer adjustment screw you should be able to adjust the trigger to the point where they will not set .
if its working for you now , great

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