I recently acquired a 686-3 with the front side plate screw missing. My research tells me that S&W re-engineered the yoke retention system on the 686-3 variant. Could someone explain what Smith changed and possibly what part(s) I'm missing? Thanks!
The yoke screw for the earlier, smaller sized screw must be fitted. In a factory setting, takes a little time; time is money. Users who disassemble the 3 sideplate screws have a tendency to be less than careful to replace them whence they removed them. "My cylinder doesn't open/close right!". The spring loaded screw solves that, except the yoke/cylinder assembly can sometimes go flying in the midst of an overly aggressive speed reload. Never happened to me and I've done 1000's of speed reloads, but I can certainly see how it could happen if the screw was a tad loose.