Take the lock off the gun, and then look closely at the engagement of the sear nose in the full cock notch. Slowly release the sear when the lock is cocked, to see what movement occurs between those two parts.
Smoothing a trigger pull Begins with polishing the faces of those two parts. Then you look at the contact point where the trigger hits the sear bar. Those two surfaces need to be polished smooth, too. Sometimes, in those guns, the trigger is just located in the wrong place, so that the trigger plate is striking the sear bar in the wrong place, causing unnecessary leverage, and a harder trigger pull. That is when You probably want to turn the gun over to a competent gunsmith to fix this.
Finally, some trigger return springs, or sear return springs, the little spring up at the top rear of the lock that is screwed to the lock plate, and has an arm that is suppose to fit in the corner of the sear, is instead hitting someplace away from the corner. If that happens, it puts resistance against your sear and trigger and increases the trigger pull. A gunsmith can fix this.
