One thing I forgot to acknowledge between the PC & non-PC revolvers:
The modern PC revolvers I've purchased new in the near past do appear to have a different hammer spring than the non-PCs.
Their springs have a groove/ridge down the middle of them where the non-PCs are flat.
People have reported these are the same ones you can get from an aftermarket vendor. (Insert name here.)
I have no first hand knowledge of this & have never played with them or compared them beyond this observation. In fact all of my S&W revolvers (except my J-frames) have factory hammer springs in them. I only replace the rebound spring & polish/smooth the internals for a better SA pull.
I still contend that if any difference exists between these two hammer springs it can be offset by other factors related to craftsmanship, fitting & machining tolerances, either favorably or negatively.
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