Are the OE S&W springs for the 4566 silver?
I purchased a used 4566 from a forum member a while back. He changed the recoil spring and hammer spring to reduced power units from Wolff which are a beep brown-bronze color. He did not note what weight was installed
Included were a silver recoil spring and hammer spring along with two more Wolff mainsprings 17 & 18 LB- also brown-bronze.
I put the silver springs in and it seems to stiffen the slide pull and hammer cocking force somewhat. If the factory springs are silver, then I'm sure that's what I installed. Was having light primer strikes and an occasional stove-pipe with the lighter springs.