Apparently, at least.
That new mainspring came, and there was suddenly no time to lose.
As simple as all those videos made it out to be. And it had a dramatic effect on the effort it took to crank the hammer back, and the subsequent DA trigger pull.
My light-hammer range queen became half exercise machine, at least by comparison. But…
It sure pops caps now. Fifty rounds of my worst fired without a single failure.
All that reading and video-watching about spring-swapping, and nobody ever seemed to want to make the springs heavier. And I think I get that – when the Model 69 was unreliable with reloads it still shot commercial ammo fine. And oh goodness was it ever a treat for making tiny groups in targets. That’s probably going to be harder now, but it’s all a matter of priorities. I don’t need a target gun, I need an EDC in a place where every now and then you really do need to shoot something. And I’ll trade a light trigger for 100% reliability with all ammo every time. So what my gun needed was to go back to something like it probably had when it was stock.
And anyway – if I really want to shoot targets, once I’ve strained my thumb cocking the hammer the single-action pull is as scary as ever at 2 to 2 1/2 pounds.
The “approved method” to reducing DA trigger press on leaf-spring S&Ws is:
Start with two mainspring tension screws, a micrometer, a 2nd cut mill file, pencil, paper, and a pile of ammo (hard primer ammo is best, CCI primers seem most sensitive, Winchester among the least, Federal seems around the middle but toward the “least” end). Including an accurate trigger pull gauge is very useful, but not required.
Measure the length of both mainspring screws with the micrometer, record their lengths, and set one mainspring screw aside and do not touch it. Install the other. test fire the revolver. If no ignition failures occur, then:
Remove the mainspring tension screw and measure the overall length; carefully reduce the length by .010″ by filing down the contact end (where the screw contacts the mainspring). Measure the new overall length and record it. Reinstall the screw, tighten, and test. If no ignition failures occur, remove the screw and repeat the procedure. Eventually, ignition failures will occur. Note the overall length of the mainspring screw. Carefully file down the second – untouched – mainspring screw to an overall length .020″ longer than the mainspring screw length which produced ignition failures. Mainspring tension with that mainspring in that gun will be reduced to the level which reduces trigger press to the greatest amount without inducing ignition failures.
Throw away the too-short mainspring screw, it’s not only now worthless, it’s dangerous to keep around. And, just to be safe, order a replacement to keep on hand, just in case.
Some advocate merely adjusting the mainspring tension screw pressure on the mainspring by backing out the screw; this works but only for a while. Without the “locking tension” of being properly installed and tightened the screw will, over time, back out further and induce ignition failures. And, since there’s no way to measure the screw length while installed, the technique has no value as a diagnostic.
Replacing the trigger reset spring will also help; Wolff Springs has them in varying spring strengths, and Jerry Miculek has a Youtube video on how to replace them easily.
Pro Tip: Springs are usually under compression or tension, and when disturbed will often fly off into an inaccessible spot. A bathtub, with the door or curtain closed is a good place to work on stuff with springs under compression, but tape over the drain first. Alternatively, a 2.5 gallon clear ziplock-style plastic bag and some paper clamps will work (it can be rolled up and stashed in your range bag). Those of us who do this sort of “spring thing” on small stuff a lot scrounge a 20-30 gallon aquarium for it, an aquarium that leaks is useless for keeping fish but fine for working on small, spring-loaded stuff – lay it on its long side, iron-on velcro tape applied to heavy canvas and around the open edge of the aquarium, to close off the opening. Two slots in the canvas provide hand access.