To lighten the pull on a revolver a reduced power hammer spring is made by Wolff..Chances are it would get the single action pull down where you might like it..It will lighten the double action pull also..
I have used only Win. primers since the mid 60's with no problems at all in any gun that I own..All have had
some easing of the trigger pull, S&W revolvers and Auto pistols,1911's,HiPowers and CZ's.. Not too light but
pleasant to use.
Use care and good judgment and all will work out well..
Generally speaking, a really good tune will give you glass smooth operation and a crisp trigger break. You'll gain a smoother action at the same trigger weight. Might be all you need. If not, go for the Spring kits, or taper grind the main spring slightly on it's two sides..
I have found over the past years, that changing the Trigger Rebound Spring to a 13# Wolff spring and keeping the stock S&W main spring, results in a lighter action, that will fire anything dependably. If you are looking for a smoother action, put about 1000 rounds through your gun. (1000 rds. of ammo ain't cheap!!! ) These two methods have worked well for me, on all my S&W revolvers. Bob
Every gun I work on uses Wolff rebound springs, but S&W full power main springs. Most K,L,N framed revolvers run 14 LB reliably. Sometimes the trigger won't return fast enough so I switch to a 15 LB spring. This will help with the DA pull and it won't affect the single action at all.
If you go 13 LB or less, you possibly will need to reduce the main spring, either by bending it or adjusting the strain screw. In changing the main you will be forced to use Federal ammo/primers only. I don't like to have possible misfires so I don't mess with the main springs. I like strong hammer springs....
On the J frame I also run 14 LB rebound springs.
The trick is to clean up all the rub points and add a few drops of oil where it is needed. Make sure the cylinder spins freely on the yoke (for the DA trigger pull only).
There are also other ways to reduce the trigger pull, even clipping a coil or to on the bolt return spring and filing the bolt (rear side of thumb piece) so the bolt will rest more rearward when the cylinder is closed will help the cylinder spin with less resistance. (Don't mess with the extractor springs inside the yoke, just tune the bolt and spring).
Only gun I won't reduce the trigger pull are the X frame 500 mags. These guns have such severe recoil they could double and any adjustments to the trigger pull could make the gun unsafe.
Check out these videos of the 500 mag doubling. Even I experienced the cylinder unlocking but traced it down to the loads and my hand pressure. (the gun bounces in your hand so quickly the trigger finger involuntarily presses on the trigger enough to unlock the cylinder).
One video if from the S&W factory as an engineer is test firing the 500 with 1 hand. Notice how the trigger finger presses down on the trigger which unlocks the cylinder. The other film is unknown if it's true or not. I believe it's factual.
I have found that 13# is the lowest that I would go, using the stock main spring. If you go much lighter. the trigger won't return properly or may not have the strength to fully cock the stock main spring. You would have to get a lighter main spring. (NOT a safe idea, IMO.)
If you use the gun for CCW, it might be a good idea to leave the trigger pull on the heavy side. You don't want an accidental discharge to occur, during a 'situation'. Remember....you are liable. :roll: Bob
A 3lbs Single Action trigger is gonna be twitchy if not done properly. It is possible, but if too much stoning is done at the wrong angle, "push-off" will occur wherein the hammer can be pushed off the SA engagement by hand.
As far as your original question, this outfit, King's Gun Works in Glendale is renown for their work.