As a kid I had a Cooey 39 but I don't remember how the triger mecanism
was made. Generaly polishing the sear surfaces and lightning the trigger
spring (removing some coils or changing to a lighter one) is the way to
obtain a better trigger pull. On my CIL/Anschutz, wich has a flat trigger
spring, I had to slightly bend the flat spring so it puts less pressure to the
trigger.
Very general but hope it may help...
Jocelyn.