I, being a nobody ski bum from a dinky little town in far, far western Wyoming think that if one inspects the NM Lockwork one can "see the light".
Examine what's going on. The hammer strikes the transfer bar and forces it into the firing pin. Just how hard does that transfer bar need hitting? Enough to batter it to pieces over time? I think not. All it does throughout its' mundane existence is support the exchange of energy from the mainspring to the firing pin. Does this poor little piece of investment cast steel need to be battered with undue stresses? Nah!
Again, my theory and my theory only. Worth about 3 nickles and a uno centavo...........
Test: Empty gun. Check. Check again. Empty? OK. Cock hammer. Squeeze trigger, pretending you are harvesting the largest Whitetail you've ever seen....
Hold the trigger back after the hammer fall instead for following your normal instinct and letting it "retract". OK, now,
take a look at that hammer "squeezing" the transfer bar against the firing pin. Slowly let the trigger go forward while watching the hammer. If the hammer moves forward as the transfer bar retracts then, In My Humble Opinion, the transfer bar was pinched. Solution? Look at the "notches" on the hammer's face. One notch is designed to handle the thickness of the transfer bar but it's usually not deep enough. Deepening the notch
just to the point that when the above test is performed the hammer does not move will reduce the battering of the transfer bar and, again, MHO, prolongs the life of the lockwork's components. ( We want the hammer to hit the cylinder frame in the hammer well at the same time it forces the transfer bar into the firing pin and the firing pin receives "full travel" into the cartridge's primer. )
I've never broken a transfer bar but, when I heard about such happenings I took a look and decided I'd try some tinkering.
I use original mainsprings in my smaller calibre stuff. but with .44 mag./ .45 Colt Rugers I'll sometimes install the Old Army mainspring. It's about 2# heavier and does a good job of "lighting caps". Of course, any undue contact of the hammer with the hammer well is fixed and any/all friction surfaces effecting the hammer's movement within the grip frame and cylinder frame are given attention.
flatgate