trigger work on a S&W 66: what to expect?

I

idek

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I'm thinking of having some trigger work done on my S&W 66 to lighten the double action trigger pull. I would be taking it to a gunsmith, and won't be doing anything myself.

I'm wondering what I can reasonably expect in terms of improvement and I'm also wondering if there's anything that can do wrong. I just want to weigh the risks vs benefits before handing over the gun and some money.
 
In my experience with the model 66 and model 19, I have found that a good polishing of bearing surfaces can do wonders for the trigger action. There are places inside of the frame, on the hammer, the trigger, and the rebound slide that can benefit from some knowledgeable and judicious polishing.
When all the tool marks which might rub are polished to a mirror surface it is nice. Even when the trigger pull is unchanged, when smoothed out it can feel lighter.

If you do not know what you are doing you can mess up the angles on the trigger and the hammer, which are critical for safe operation though.

A competent gunsmith should know where and how much to polish and keep the works safe.
 
The benefits are worth the time and cost. There will be no "risk" unless you take it to a hack smith. The difference between a stock S&W action and a tuned one is HUGE.
 
The "risk" is the possibility of getting too light a trigger pull with the resulting light hammer fall. This can lead to light strikes which cause misfires. I have never had an action job on a Smith & Wesson revolver.

Bob Wright
 
The mainspring is what controls the ignition of the primers. The rebound spring can be lightened considerably and cannot cause light strikes...it just controls trigger reset and adds significantly to the force required to fire the gun if too heavy (and they all come too heavy).
The works of S&W's these days are rougher than a cobb. I have had them come with triggers dragging on the side of the frame, hammers that strike the frame when dropping, the hammer bosses rough (machine marks digging into the adjacent area of the hammer). It is well worth the while to get some trigger and hammer pivot shims to straighten those so they do not contact the frame as part of a smooth-up job.
In most cases, the contact surfaces and angles between the trigger and the hammer are fine the way they come and do not need to be touched.
 
Idek:

I have a Smith & Wesson model 625 that i had a professional gun smith work over. When it was returned the trigger and action was butter smooth. It will put any Colt Python to shame.

Semper Fi.

Gunnery Sergeant
Clifford L. Hughes
USMC Retired
 
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I'm wondering what I can reasonably expect in terms of improvement and I'm also wondering if there's anything that can do wrong. I just want to weigh the risks vs benefits before handing over the gun and some money.
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Not knowing how your trigger is now, and what you want, it is difficult to answer this question. An action job should be tailored to the purpose of the weapon. For example, I have a 625 that is super smooth, but produces light strikes in double action on some brands of ammo. However, the intent of the gun is for range use, so it does the job I want it to do (when using federal primers it has never misfired).

An action job for a home defense/carry revolver is going feel different. It is imperative that you tell your smith what you are going to use the revolver for, and what you want out of the trigger job. If you aren't familiar enough with revolvers, you might ask the smith to give you some examples of his work, or find a revolver freak who will let you pull some of his revolvers' triggers.

As to what could go wrong, well a lot could go wrong. Take your gun to a good smith and most likely nothing will go wrong, although even good smiths can have bad days, so test it thoroughly after getting it back to make sure it functions to your liking.

The more likely screw up is that you will not communicate what you want to your smith. I know, I've done it myself.
 
If the gun is for defense it's best not to lighten the springs, just shoot it and it'll smooth up or it can be polished to smooth it up faster. I have a range guns that have lighter springs in them. One is only reliable with Federal primers, it might shoot Remington factory. A couple others work with any primers, a couple have light rebound springs, I have failed to let the trigger go all the way forward when firing rapid fire. Bottom line is if it's a fun gun have at it. If it's a SD gun be careful.
 
Not knowing how your trigger is now, and what you want, it is difficult to answer this question.
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I mostly shoot the gun just for fun, but if I were to use a handgun for HD (my first choice is my shotgun), this would be it. So I'd prefer not compromising reliability. Right now the gun has about a 12 lb. DA trigger pull.
 
I mostly shoot the gun just for fun, but if I were to use a handgun for HD (my first choice is my shotgun), this would be it. So I'd prefer not compromising reliability. Right now the gun has about a 12 lb. DA trigger pull.
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A good 'smith can smooth the action nicely, and even with stock springs it'll feel a bit lighter. Fortunately, smooth is much more important than light. You (i.e. the 'smith) can drop the pull weight a bit without affecting reliability, but be sure to tell them your needs ahead of time. BTW, you can drop the pull weight further without loss of reliability by bobbing the hammer & converting to DAO.

The rebound spring can be lightened considerably and cannot cause light strikes...it just controls trigger reset and adds significantly to the force required to fire the gun if too heavy (and they all come too heavy).
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Technically, this is true, but there's not much latitude here if the mainspring remains stock. Keep in mind the rebound spring is what rebounds the hammer, so it has to push back against the mainspring. Too light, and the return becomes sluggish, and greatly increases the chance of a short-stroke. It's best to keep the main & return springs balanced.
 
Thanks for all the replies. Based on what you've told me, I'll probably just see what can be accomplished without changing springs.
 
Idek - yes, an action job can greatly improve your Model 66 trigger pull.

MrBorland hit the nail on the head with "smooth is more important than light."

I don't agree with the premise that you shouldn't even consider changing springs. It depends in part on what your double action trigger pull measures now. If it's already 10 pounds or less, you probably should leave the springs alone. OTOH if it's over 12 pounds, you should at least consider reduced power springs IMHO.

Wolff Springs offers two mainsprings for S&W revolvers, standard and reduced power. For a possible defense gun, sticking with the standard power makes sense. It still may lighten your trigger pull but it won't compromise hammer energy as far as I can tell. That's what Wolff will tell you too. Factory springs aren't all that consistent IME. For example, I have a 25-2 where the standard power Wolff spring increased the trigger pull. I've had two 66-2 revolvers where in one the standard spring hardly made a difference and another where it defintely reduced the trigger pull down to just under 12 pounds.

As far as the rebound spring goes, I don't think a 15 or 16 pound spring compromises function (stock is 18 pounds). 14 pounds is ok in some guns and iffy in others. 13 pounds would be ok only with a reduced power mainspring and for a range-only gun.
 
You can also learn how to do it yourself ...Jerry Miculek has a very good DVD out on how to do a trigger job on a S&W revoler...( available thru Brownells and others )....its pretty easy to do / Brownells has spring kits for the K frames as well....

Sometimes just removing the side plate / and lubricating things properly is all it needs. You need to remove the side plate properly ...but again all this stuff is not that hard.
 
It is entirely possible to do the job yourself; to do it properly, and to save a ton of money.

First step:

Purchase and read Jerry Kuhnhausen's Shop Manual on Smith and Wesson Revolvers. AFTER you complete this step, move on to the next one.

Step two:

You will need the following:

1. JB Bore Bright compound.
2. Wolff rebound springs. They are available in different spring rates--I purchased a calibration pack.
3. PROPERLY sized screwdrivers for the Smith and Wesson screws.
4. A Wolff Power Rib mainspring. You can find it at: http://www.gunsprings.com/index.cfm?page=items&cID=3&mID=58
5. A good medium weight lubricant.

Begin by properly clearing the revolver. Now, remove the cylinder.

Next, remove the grip panels and the sideplate.

Loosen the strain screw, and remove the mainspring.

Pull and hold the trigger to the rear, and remove the hammer.

Next, remove the rebound slide. (HINT: Wear some gloves, and put your thumb over the end of the rebound slide to catch the spring. It comes out with a bit of force, so be careful!)

Now, thoroughly clean the inside of the frame. Replace the rebound spring with a lighter Wolff rebound spring. Factory weight is around 16lb; I use 14 lb. springs in mine.

Before assembly, coat the bottom shelf where the rebound slide rests, and the inside of the frame next to the rebound slide with JB Bore Bright and a bit of oil. Reassemble the rebound slide assembly into the revolver.

Now, while holding light pressure on the top of the rebound slide, cycle the trigger 30-40 times.

Remove the rebound slide again, and clean thoroughly. Now, reassemble fully. Take care to ensure that the trigger plunger seats fully in the front of the rebound slide. Lube with good oil.

Finally, replace the mainspring with the Power Rib mainspring. Always use an UNALTERED strain screw.

My 686 has a 10 lb smooth double action pull that is 100% reliable; single action pull is 2 lb. Again, it is absolutely reliable.

NEVER, EVER, EVER, touch the engagement surfaces--sear notch, sear nose, trigger shelf, camming notch or sear edge--on a Smith and Wesson. The heat treatment is very thin--and polishing these surfaces will destroy the heat treatment.

Remember--get Jerry Kuhnhausen's book first.

Good luck!
 
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