I replaced the stock rebound spring with the one from a Miculek kit, and it resulted in a surprisingly noticeable improvement in perceived trigger pull. During my experimenting, I went back to the stock ribbed mainspring in this 627PC, because installing the Miculek main spring along with the reduced power rebound spring resulted in a sluggish trigger reset.

So, now I'm very happy with the combination of the stock PC ribbed mainspring and the Miculek rebound spring... I'm wondering - is there any downside to this lighter rebound spring? The trigger resets just fine, even when the gun has been shot a lot and is getting dirty, so I can't think of any reason this would turn out bad for me in terms of reliability.

By the way, does anyone know the spring weights in Miculek's kits made by "Bang"?

The trigger rebound spring and mainspring must be "balanced" for things to work right.

I used a Wilson Combat mainspring and Wilson 12# rebound spring in my 10-14 and it works perfectly.

I looked at the Bang Miculek set, but I don't have a gun that needs light springs right now. The ad says they are "balanced" to work in perfect unison for an ultra smooth stage free DA pull.

I had a stock mainspring and an 11# rebound spring in a 10-5 and the trigger would not return.

I also have a stock mainspring and the same 11# rebound spring in my Single Action Only Model 14, and the trigger "just" snaps back. It depends on the gun, if the action has been polished, etc. This 14 is highly tuned and there is less "resistance" in the action so I can get away with the lightest mainspring. A bone stock 10-5 did not like it, because the action had not been polished. I do not mind the weak return on a Single Action only target gun like my 14, since it is for range use only and I would never rely on it for defense.

All of my "range guns" have light rebound springs.......but ALL of the revolvers I use for CC or HD, if only occasionally, have stock rebound springs and stock mainsprings. If you use a revolver for defense that you may need to save your life one day, I strongly recommend keeping the springs stock. You don't want that trigger to fail to return when you are trying to stop a threat.

For a defense gun, smooth is what you want. I suppose one could get away with one or two pounds lighter and maintain reliability but I'm not willing to do that.

__________________
Centennial Every Day

In fact, you want a carry gun to be as stock as possible. Plan for the worst casr scenario, that you'll be picked apart in court, and you want to give the liberal anti-gun soccer mom prosecutor as little to use against you as possible. If they have an expert witness (i.e. a local gunsmith) say that your gun was "altered" and has a "hair trigger" it will look worse.

The 10-10 I keep in my "car safe" has a heavy mainspring made for modern MIM and frame mounted firing pin S&W's, as well as a new, heavy rebound spring. It's still a smooth, but heavy pull in DA,and SA is heavy too....... but there's NO way anyone could ever say it's been altered or has a "hair trigger".

I also carry one of my stock Ruger Service Sixes a lot, and anyone who owns a bone stock Ruger DA revolver knows that there's no way the trigger pull can be described as light.

There are 2 reasons for not going too light on the rebound spring.

One is that you may experience a sluggish or failed trigger return. If the trigger doesn't return fully it can completely tie up the lockwork. In addition a sluggish trigger return can slow the firing rate noticeably.

The other reason is that a light rebound spring will lighten the single action trigger pull. In a gun that a previous owner has stoned the sear on the trigger, a 12 lbs. rebound spring can result in a sub 2 lbs. single action trigger.

BTW, I've done some controlled experiments on the triggers of a 67-1, 617, 610-3, and 620. For a basic rule of thumb a 14 lbs. rebound spring will result in a SA trigger pull just over 3 lbs. if the sear on the trigger hasn't been messed with. A 12 lbs. rebound spring will take the SA pull to the region of 2.5 lbs. If someone has tinkered with the sear on the trigger, a 12 lbs. rebound spring can result in a SA pull of ony 1.5 lbs.

On the double action side, the effect of changing the rebound spring really isn't noticeable. I've experimented with rebound springs from 12 to 15 lbs. in my 620 and when measuring the DA pull with a Lyman digital trigger gage the change in weight fell within the range of variation for a series of trial pulls. The average weight may have fallen by perhaps as much as 1/2 lbs. but IMO anything lighter that 13 lbs. really isn't beneficial. As for why the difference is so slight, my hunch is that the position of the trigger relative to the position of the toggle link that drives the rebound slide masks the effect of a lighter rebound spring. Basically at the start of the trigger pull most of the weight is controlled by the mainspring acting on the hammer and at the end of the trigger stroke that toggle is so nearly straight on to the rebound slide that all you can feel is that fully tensioned mainspring. I was a bit surprized by this but after seeing the same behavior in 4 seperate revolvers I've come to the conclusion that the weight of the rebound spring has little effect on DA pull if your running a trigger over 7 lbs.

Now, Bullseye may take exception to this, however he's running guns with ball bearing lockworks and a sub 4 lbs. DA pull. On a gun with that state of tuning I suspect that a change in the weight of the rebound spring would have a measureable effect.

Personally, I prefer a 14 lbs. rebound spring over any other weight. With the exception of my 617, which needs to have the trigger sear sharpened, it's resulted in a SA trigger between 3 lbs. 2 ounces and 3 lbs. 4 ounces. That is right where I like my single action trigger to break.

As for the mainspring, all 4 of my guns are using the factory mainspring and I've done my adjustment for weight by shimming the position of the strain screw. I've also found that Target hammers actually require MORE power from the mainspring than Service hammers. While that seems counter to conventional wisdom, my testing has indicated that primer ignition is a function of Kenetic Energy, NOT momentum. Since velocity is squared when determining Ke, a lighter hammer moving faster can produce the same energy as a heavier hammer moving slower. Heavier hammers require more power to get up to speed, so you need more power in the mainspring.

Finally, there is more to ignition than just the round firing. I've determine that you can have the reliable ignition but see an observable loss in accuracy when you lighten the trigger in controlled steps. When I first took the trigger on my 620 to 8 lbs. the ignition was perfectly reliable with Speer Lawman, however the groups had doubled in size compared to what I saw when it was set to 9 lbs. I also saw groups that were vertically oriented, an indication of a variation in velocity. Fortunately, simply installing the extended length firing pin from Cylinder and Slide brought that accuracy back to where it was with the trigger at 9 lbs. IMO that is one distinct advantage to the frame mounted firing pins, it gives you tuning options that were lacking with the hammer mounted firing pins.

Now, to sum things up. Once you've bee "bit" by the tuning bug the urge to improve won't go away. I would advise that once you start tuning for a lighter trigger to plan on doing some Benchrest shooting for accuracy. Once you start to see the accuracy falling off, either go back to the previous weight or install an extended firing pin from Cylinder & Slide or Apex Tactical. BTW, I do NOT endorse using one of these firing pins in a gun that has not been tuned for a lighter DA trigger, when I tried the C&S firing pin in my bone stock 610 I saw evidence of primer leakage at a 30% rate and cracking in the primer dimples under magnification on those primers that leaked. Now that the 610 has been tuned to a 9 lbs. trigger, that primer leakage issue has gone away.

No offense Stan but I just don't buy it. If the shooting is justified it won't matter if you had different springs in your gun and if it wasn't justified...it won't matter if you had different springs in your gun.

Dave

__________________
RSVN '69-'71
PCSD (Ret)

I agree. If its justified, its justified.

You think that way, and I do, too. I agree with you, it shouldn't make any difference.

But why take a chance with the 12 people sitting in the jury box, who may be inclined to buy the soccer mom DA's "you altered that gun, didn't you" argument?

Hey guys, thank you for all the great information. I am looking ONLY for technical advice - please feel free to start a different thread on the legal issues.

Scooter - thank you for the detailed data on your experiences. I've seen several other threads where you discuss these details and I've got a bunch book marked as I begin to learn about the guts of my revolvers. I was especially surprised to see a reference to accuracy degradation with springs that are too light. I guess that is due to inconsistent quality of primer ignition - right? I never thought of that...

Someone here mentioned the "balance" between rebound and main springs. My only technical reference, the Kuhnhausen manual, does not use this terminology. Is there a certain measurable metric to determine "balance", or is this a reference to making sure the gun works and feels as it should?

I've bought and installed Wolfe spring kits in some guns and had left-over lighter rebound springs (14 and 15 pounds, I think). I have routinely used these in other guns without a matching mainspring and never had any problems. I can't say it made a noticable difference in either SA or DA trigger pull, but when I buy a new (to me) used S&W I usually disassemble it, stone the slide, and install the new spring.

Don't want to start a "legal" debate, just trying to share what I have been told by the people who would probably be dealing with my case if I ever had to shoot in self defense......

It may be different where you live, alter your carry gun and take the added risk if you think a little bit lighter trigger pull is worth it....I work with and talk to my County DA, the Sheriff and lots of other local govt. people every day, I work at my county courthouse and sometimes the subject of armed defense comes up. The local magistrate judge carries a Ruger SR9, and a deputy Sheriff I was talking to carries a new S&W Bodyguard .38 as his off duty gun.

Not saying they're "right" and it may not be what some people want to hear...... but I'm saying what they have told me, pretty much they say "don't carry a tuned up handgun and don't carry anything that says "Magnum" on it".They tell me to just carry a Glock .40, because that's what all the local Police and Deputy Sheriff's carry...but I carry revolvers....to that they say "then just carry a .38"...not everyone, including LEO's, is a "gun person".... Again, not that it's right, but it's the way the judicial sytem in my area works. If things go really bad, the bad guy you shoot survives and some how casts some shadow of a doubt on the "justified" thing, you will be judged by 12 of your peers....or if God Forbid you hit an innocent bystander with your slicked up .357 ......you can't pick which of those peers will be judging you, they may be anti-gun, pro-gun, indifferent........ The courts may also have an "expert" examine the gun that the police will have taken from you after the justified shooting, that expert could be Homer the local gunsmith,or a local PD armorer.... "Yep, this guns been tuned up, got a hair trigger and it was loaded with hollow point .357" He'll probably use a $10 Lyman trigger gauge, and compare your pull wieghts with factory specs he finds on the internet, to come up with his decision.

Even in the most justified shooting, you may be forced to defend yourself in court. I don't know, every case will be different. There is no "blueprint" to how it will all go down. Me personally, I feel having a stock 6-shot .38 revolver with stock springs leaves me less open for "interpretation".....no one can call me a "commando with a hi-cap mag" or accuse me of having a "gun modified expressly for killing people". I used to carry a Ruger Service Six or Speed Six loaded with .357's all the time, but I have now switched to Model 10's and 64's or a Service Six chambered for .38 Special only. This is the reason the NYPD authorized only DAO revolvers in .38 with heavy springs, to reduce issues with legalities and accidental shootings.

You can be seen as an ordinary citizen with "an old .38 police revolver" who was in fear of his life and forced to shoot........or you can be painted by the scumbags anti-gun Public Defender as a "vigilante with a hair-trigger gun altered for gunfighting, shooting high-powered Magnum hollow point ammunition........this guy was looking for a fight" and the jury will be like "Wow he had a Magnum......."

As a CCW holder, sure you can carry any handgun you want, I know a guy who carries a Ruger Alaskan .454......but if he ever has to use it and someone innocent gets hurt, well, good luck to him......

while i agree. let us not forget about when the civil case comes up which requires less to prove their case.

__________________
balin
NRA Life Member

Guys, thanks a lot for the feedback. This thread is for TECHNICAL discussion only, please start another thread regarding legal issues.

My experience indicates that lighter rebound springs require that more attention be paid to reducing friction on the internal components, most specifically the trigger, rebound slide, and the cylinder stop. Fail to do that and the result can be a jammed up gun.

When I first started experimenting with my 610 I tried a 12 lbs. rebound spring in it and it locked up completely on 2 seperate occasions in live fire testing, testing with snap caps it was 100% perfect in function. I also found that pushing the trigger forward didn't free up the lockwork, I had to spend a bit of time wiggling the hammer forward and back while applying slight pressure to the trigger. I suspect that the drive link for the rebound slide had popped out of position and the rebound slide was jammed in a position where the hammer couldn't move. Since then I've spent a bit more time in smoothing the area for the rebound slide and stoned the slide a bit more, however because I didn't like the weight of the trigger in single action it now has a 14 lbs. rebound spring installed. Good news is that bit of additional work has resulted in my 610 having an exceptionally smooth trigger in double action, so the 9 lbs. weight really isn't at all difficult to shoot well with.

The "balance" means that if the mainspring is heavier than the rebound spring will allow, it is out of balance and the trigger will not return.

The kits like the Miculek and Wilson Combat mainspring-rebound spring kits are meant for guns that will also be tuned up, have the wear surfaces polished and stoned, and the friction reduced.

I lubed up some of my revolvers with moly, and it slicked them up pretty good. Moly penetrates the pores of the metal, and reduces friction and will allow lighter springs to work better.

In my experience, I am not a good enough shot to really see any benefit from slicking up my revolvers. I have a bone stock Ruger Speed Six that I shoot better than some of my S&W's that have been "worked". My slicked up 10-14 shoots marginally better than my police trade in 64-7 which has heavy springs.

What was said by scooter is true, the gun may jam up with live rounds but work fine in dry fire. I put light springs in a DAO 10-10, worked fine with no rounds in it, took it to the range and the first shot jammed the gun up......the firing pin got stuck in the primer and the lighter rebound spring didn't have the force needed to return it. I put the stock springs back in and it worked 100%.

Overall, decide how important a little bit of a lighter DA and SA pull is to you and how much you will actually benefit from it. We all like to tinker, but I have learned that if it works with the stock springs, I usually just leave it alone. Unless you're shooting in matches like PPC or Bullseye and need a slick DA pull or ultra light SA break to take 1/4" off your groups, it won't be the night and day difference you may expect.

As long as the trigger will reset your fine. Going very light will require some skills.

Do not lighten the trigger on the X frame. M500 revolvers can double which could kill someone.

search youtube for 500 doubles, very scary stuff having a bullet graze your nose.....

__________________
NRA Benefactor Member

Scooter you mention "ball bearing lockworks" I assume that was as an adjective and not to be taken literally, eh?

I was wondering that too. Ball bearing works would be nice :-)

In the past there have been gunsmith's who have actually installed ball bearings on the pivots for the hammer and trigger. Bullseye Smith recently posted his results for tuning one of his revolvers to a 3.8 lbs. DA pull and I suspect that ball bearings were used to achieve this level of tuning. I also have a sneaking hunch that he's installing miniature thrust bearings on the hammer at the same time, but that's pure speculation. To be totally blunt, I'm just burning with curiosity as to how he's getting reliable ignition with a DA trigger that light but suspect it's well beyond the capacity of us simple mortals.

So, in answer to your question, it wasn't a "tongue and cheek" comment, there are some revolvers in existance that used ball bearings in some areas of the lockwork. A few months back a member posted pics of what I remember as a King tuned S&W and my meory is that it featured a ball or needle bearing on the hammer. If it was a King tuned revolver, that would date to the 20's or 30's, so it's not exactly new. Basically, the quest to improve never ends, it just moves on to new materials or methods.

The Dan Wesson uses a ball bearing for rear cylinder lockup.

I have 2 Dan Wessons, while I wouldn't use them for defense they are as close to an out of the box tuned up match revolver as it can get. My Model 15 .357 Dan Wesson is very accurate, but the trigger reset is lighter than I would like. It's a great range gun, but I have no need to carry it.

After using my "high end smith/competitor tuned" 627 for several years with the work he did on the trigger, it began to exhibit progressively more crepetations and glitches in trigger-return mode. Despite 'cleaning & oiling' finally it got downright cranky and would have definite hesitation that became a predictable failure of trigger return about 30% of the time and which I could aggravate by slow-return with careful trigger pressure as in dry fire exercise or to show someone.

Trying to figure this out and after major break=down & clean~desperately needed for sure~I put in a 11# spring.....replacing the 15 coil shortened one it came with.

That made it WORSE.

Obviously I was working under an erroneous premise.

Pondering overnight, I was struck by finally realizing it was telling me a stronger spring was in order.

I put in the 13# Wilson, and VOILA!!!!

All is right in the 627 world now. In fact, I believe it is better than when I got it. Perhaps practice/familiarity has helped.

The only light primer strikes I ever got in it was the time I forgot to tighten the strain screw properly. And yes, pay attention to the little Torx set-screw that locks it in place. IIRC it's about a T2 or T3...mighty small, had to buy a whole set of the little Torx to get one that fit.

So yes, make sure your rebound spring is not TOO light.

__________________
Dum vivimus Vivamas

get the wolf springs kits and play around with them until you find what you're looking for. that's what i did with my 66-1 and it's very smooth and just a bit lighter.

did the same with my 66-2 and it's very smooth

Does one need a special tool to change the rebound spring?

i use a allen wrench the same size as the spring to compress it...

I don't use "Ball Bearings" I use "bearings", They look like a shim. If you think about they are a shim . But they also act like a bearing. The big thing is drag, one burr can cause alot of drag, two will double that. The more drag to cut the less power it takes to work it. Trying to get things fitted is sometimes a problem for me, The MIM parts are way easier to get down to a low drag. You don't remove but a very little material to cut drag, no even a .001 of a inch. The stud that the hammer and trigger set on have alot of drag, take your finger and go around the stud base and on the side plate and you will fell the burrs that cause drag. The stud itself is ruff, use the back side of emery cloth and a little polish compound and then feel it , no material removed but the small unseen burr's. But you can feel the differents, then do the inside and the side plate. Then you get into the hammer and trigger, go around the outside edge with a very fine file and then 1500 paper, and you do this by feel and you do it very lite. Take a 1/8" bit and wrap a piece of 1500 with a lite oil on it a do the hole in the hammer and use a 1/16" bit to do the trigger, you do this very lite, just enought to get the burrs out. I going to stop here, but to do a good action job is a slow drawed out thing that 99% don't want to spend the time to do it. I don't know everthing about a Smith & Wesson, I learn something every day. I wish I could shoot better than I can work on them, shot my 32 today and at 25 yards i couldn't get pass 84 points out of a hundred in slow fire.

gr7070 - a special tool is not required, but I highly recommend it. It is pretty cheap at Brownells, and it'll pay for itself the first time you use it and NOT launch the rebound spring into oblivion. Or into your face... :-)

Bullseye, take a look at the following link, might set some wheels spinning.

Bearing Search Results | NTN Bearing Corporation of America

Yeah, it's Metric and I'll admit to not having measured the hammer stud. However, S&W has gone to Metric sideplate screws so there is a chance the hammer stud is metric. If so, you'll see why I suspected that you might be equipping some of your guns with roller bearings.

Bearing Search Results | NTN Bearing Corporation of America

Fact is that I've been pondering on trying to build a roller bearing lockwork, roller bearings have gotten really tiny and it wouldn't be too difficult to have a hammer jig ground to install one of these bearings. I also have one application at work that uses loose needles on a 1.5mm pin to provide a roller bearing, BTW, it's a huge PITA to put one of these together but it can be done using grease as a "binder".

I saved it, and will work on it.

Much thanks y'all! For a couple bucks I'll add it to my next order.

I recall Cylinder and Slide offering a DAO conversion kit for S&W revolvers (L frames, maybe K frames) that used a roller bearing of some kind mated between the hammer and trigger for a smoother and lighter trigger pull, if I remember correctly. Is that kit still around?

Even though my 637 and SP101 worked ok with lighter springs I always had this concern hanging over my head about all the things mentioned in this thread and others. So tonight I put the stock springs back in both revolvers and have that reliable feeling back. I've been using those hand grip squeeze exercise things and both guns don't feel so tuff to operate now. Just thought I'd throw in my two cents. Have a good night.

I would like to learn more about how a 500 can "double."

Dave Sinko

[QUOTE=scooter123;135887828]There are 2 reasons for not going too light on the rebound spring.

One is that you may experience a sluggish or failed trigger return. If the trigger doesn't return fully it can completely tie up the lockwork. In addition a sluggish trigger return can slow the firing rate noticeably.
........


Thank You!

I don't think they still have that kit. You could look on the website. I installed one of those. The ball bearing on the DA sear just has a flat piece of steel wrapped around for the outer race. After using it for a while, the ends start coming undone and the bearing falls apart. I replaced it with a solid bearing made of hardened tool steel that worked fine. In the end, I didn't feel that the action was much different than without it.

In related news, I have a new development in the works that should be out before the end of the year that some may find interesting.

__________________
protocalldesign.com

There have been 2 cases that I know of (might be more) where someone has blown their head off when a 500 doubled on them. The way I understand it is like this:

The gun fires with great recoil, pushing the gun back in the hand and the trigger finger is off the trigger, allowing it to reset. As the gun flips up and back, the shooter's hand closes back on the gun, attempting to hang on to it. In the process, the trigger is pulled a second time, and the gun fires again. All this happens in a fraction of a second.

If you, or anyone you know wants to shoot a 500 or 460 for the first time, PLEASE only load one round at a time! Your life or theirs may depend on it.

__________________
protocalldesign.com

In my 5"629 "Classic" .44mag, I use an 11 lb rebound spring, and a stock mainspring. I shoot single action exclusively, and I want the lightest possible SA trigger. No problems at all.