When I got the 52, the rear sight would loosen up a little bit after 75 - 100 rounds. The Novak sights have a small set screw. Anyway, to make a long story short, I couldn't get the firing pin out and finally figured out that the set screw has to be backed out first (seems I've seen some old S&Ws that way). the other interesting thing I found was a hole drilled through the slide for a longer spring. I switched out th firing pin for a Harrington #1. The trigger pull with either pin is around 31/2 lbs. While I was messing with the firing pin I wanted to look at the sight just for curiosity. Didn.t come out too hard, so I cleaned everything up and put er back together- everything has to be just right or the trigger would bind.
If you can find the sights, I highly recommend them. My son can hit a clay pigeon turned on edge at 30 yards repeatedly!