I agree with Mike, most triggers can be lightened by (juducious) polishing of the articulating surfaces. Parker triggers are relatively easy to work on. Lay it on the left side with trigger pointing toward you. Remove the screws that hold the two pieces of the housing togehter. Study how the parts interact. Take it very slow and polish the points of contact, keeping the same angle, rather than removing metal. In most cases casting marks will show you what needs polishing. I've used a fine diamond lap and fine 'trigger stones' with great success. You may also need to lighten the trigger spring by replacing the original with a piece of one from a ballpoint pen, for example.