4006 tsw reduced power hammer spring?

Doc1500

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I just received a 17 # reduced power hammer spring from numrich.
It's about a quarter inch longer than the one that is in the pistol. I'm guessing the one that was in it is squashed?
This is a CHP model.
Using the new spring the DA trigger pull weight was only reduced 6 oz. Sa 4oz.
Perceived trigger pull doesn't seem to have been reduced . thoughts and comments please.
 
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Wolff says 20 is standard. It is common for a reduced spring to be of finer wire at a longer free length. Or, yours could be squashed into a set length.

I figure there is so much friction and lack of mechanical advantage that a change in spring made little difference.
 
A couple thoughts on using reduced power mainsprings in 3rd gens. (Yes, I've tried it at various times.)

The factory mainsprings offer what the engineers decided was an acceptable potential to ignite primers that may be "hard", and also maintain sufficient power to drive the hammer forward under some adverse conditions. Think of the firing pin channel becoming fouled due to the excessive application of cleaners and/or lubricants that migrate into it (with your first clue being occasional light-strikes), or a situation resulting in an unexpected contamination (submersion of gun) that may also impair firing pin movement.

Both the recoil spring and the mainspring are involved in rearward slide travel during cycling. Changing one or the other may introduce a change in the "balance" of things, such as during recoil when the slide is running to the rear. The mainspring resists the hammer being lowered by the slide when the slide is running to the rear. From what I've been told over the years, a lighter mainspring may allow more bounce to occur when the hammer is cammed down by the slide (meaning the hammer bouncing down and then up to catch in SA).

After having tried some reduced power mainsprings over the years, I prefer to use factory mainsprings in my 3rd gen guns.

If this is just a range leisure or competition gun that's one thing (and discussing your preferences and usage of the gun with a good smith might be helpful). However, if it's going to serve as a dedicated defensive weapon, the stock configuration (recoil & mainsprings) offer some reliability advantages.

Another spring some 3rd gen owners like to fiddle with is the drawbar plunger spring. Reducing the power of that spring might offer some advantage in minimally reducing DA trigger pull for a competition gun, but it also reduces the power of the drawbar being returned forward. Contamination of the spring's channel might become an issue with a lighter rated spring.

Also, if lighter spring makes the trigger recovery feel sluggish, it might slow being able to fire subsequent shots. Then, as the spring becomes even lighter with use, it might end up not properly "powering" the drawbar to lift up and engage the DA notches of the hammer, causing a Skips-DA condition.

FWIW, I've never worn out a factory mainspring or drawbar plunger spring, nor have I had to replace any of either spring in the 500+ early production 3rd gen duty weapons I helped support, and then the new production TSW's that replaced them.

I have, however, had a reduced power drawbar plunger spring become weakened to the point it started causing Skips-DA problems. The drawbar tail wasn't lifted high enough to engage the hammer's DA notches, and the hammer began erratically falling too soon during the DA trigger pull, providing insufficient hammer force to ignite a round. No more reduced power drawbar plunger springs in my working or personal 3rd gen guns.

Unless you have a physical condition that prevents it, you might consider hand and (index) finger strength exercises. I do, especially as I'm growing older and having to work harder to maintain strength.
 
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Wolff says 20 is standard. It is common for a reduced spring to be of finer wire at a longer free length. Or, yours could be squashed into a set length.

I figure there is so much friction and lack of mechanical advantage that a change in spring made little difference.
The Standard Spring may not be standard because it is a CHP model. Don't know if CHP had this particular pistol made with a lighter spring.
What friction would you be speaking of? Meaning the hammer strut inside the spring friction?
I did polish the hammer strut but not the inside of this particular spring I may do that.
If the standard is 20 and I put in a 17 one would think that it would reduce the da trigger pull a little more than a third of a pound.
I'm hoping some CHP gunsmiths /armorer's would chime in please .
And I have completely disassemble this pistol and Polished every metal-to-metal contact point there is, except for metal surfaces inside the frame.
 
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I don't have a parts list more current than late 2013, but the original M4006CHP and the late production 4006TSW had the same mainspring (also used in the full-size 9/.45 TSW's, BTW).

The factory had 3 sizes of mainsprings. Full-size, Compact and the Chiefs Special series (really short).

One of our forum members is a smith for the CHP, and he would be better able to say whether the M4006TSW's that replaced their original M4006's had a special order mainspring. Considering most agencies (and especially the CHP) like to err on the conservative side of things when it comes to safety, reliability and functioning, I'd not be surprised if the CHP stayed with the factory spec original mainsprings in the late production .40's, though.

FWIW, the later production 3rd gen's, including the newer TSW's, had the advantages of smoother hammer faces, sear noses, trigger prongs, drawbars, mainspring plungers (cups) and drawbar plungers. Even the hammer stirrups I saw were better finished (stamped part), with less burrs along the edges that rode inside the mainsprings. Pretty much they offered most users "better triggers" than the older 3rd gen guns. (DON'T "polish" spring coils, BTW.)

Obviously, it's your gun and not mine, nor am I responsible for it''s service and maintenance, but if it were mine I'd stick with stock if I were going to carry it and use it for a general defensive role. It's an example of the latest production methods, manufacturing techniques and design revisions in the long running S&W metal pistols (1st, 2nd & 3rd gen).

Just my thoughts, though. I'm only a S&W trained 3rd gen armorer, user and owner, meaning I'm NOT either a gunsmith nor a S&W factory repair tech.
 
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Fastbolt, the DAO 3rd gens comes with a 17 lb mainsprings from the factory. Are those guns any different internally than standard 3rd gens to allow reliability with a lighter hammer spring?

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Fastbolt, the DAO 3rd gens comes with a 17 lb mainsprings from the factory. Are those guns any different internally than standard 3rd gens to allow reliability with a lighter hammer spring?

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Some of the much older DAO's were reportedly said to have sometimes been produced with a lighter mainspring. I've heard/read that stated by someone outside S&W, but not from within S&W. Dunno if it's correct.

However, if you browse the factory parts lists for all the 3rd gen guns you'll note that the same mainspring part number is used across the full-size model lines in 9/.40 & .45 guns (except for one odd .45 model that listed a different mainspring than the others I checked). I didn't see any "optional" mainsprings for models, either.

I once asked one of the factory guys who taught one of my 3rd gen armorer classes about the listing of the lighter mainspring referred to in a website for an outside spring maker, but he said he'd never known of one being used, himself. (Certainly not impossible for someone at the factory to be unaware of some specially spec'd model production run, though.) The use of a lighter factory mainspring has never been mentioned in any of the armorer classes I've done for the TDA/DAO guns, either, or in the armorer manuals provided. Granted, I only took that class 4 times, so it might've been covered in a much earlier class. Dunno.

Never-say-never is part of the business model for S&W, though.
 
If you polish the outside rails of the drawbar it will give you few more pounds off with out the worry of light primer strikes.
 
Hi, Doc1500!

If I haven't said it yet, Welcome to the Forum!

Re: Reduced power Main (hammer) springs for CHP4006TSW models, there is a Forum member whose handle is: adrianolsen.

He reports that he is a CHP Gunsmith.

In posts #36-#39 of this attached thread: http://smith-wessonforum.com/smith-...9-anybody-have-chp-4006-a.html?highlight=spin he speaks to your issue.

From what I understand, you may not have a "standard" main spring in your pistol. ;)

John
 
Hi, Doc1500!

If I haven't said it yet, Welcome to the Forum!

Re: Reduced power Main (hammer) springs for CHP4006TSW models, there is a Forum member whose handle is: adrianolsen.

He reports that he is a CHP Gunsmith.

In posts #36-#39 of this attached thread: http://smith-wessonforum.com/smith-...9-anybody-have-chp-4006-a.html?highlight=spin he speaks to your issue.

From what I understand, you may not have a "standard" main spring in your pistol. ;)

John

His specs for the DA/SA trigger pull @ S.A 6-7, D.A 12-14 are approx what you'd expect with a stock spring. FWIW, that's slightly heavier on both pulls than the standard SIG - off the top of my memory, without pulling the armorer manual or notes - which would be SA-4.5lbs & DA-10lbs.

The CHP smith in the other thread does a good job of explaining the potential dangers of improperly grinding (spinning) the mainspring to reduce wire gauge and weaken spring.

Factory springs are "closed", meaning the coil end windings are flattened, "closing" the end coils against the next-to-the-end coil windings. If using a spring with "open" coil ends, or clipping a stock spring, you'd not want to have a burred end chew into the nylon mainspring plunger(cup) or be positioned weird under the shoulders of the top of the stirrup.

If a slight reduction in DA trigger pull is worth a possible reduction in reliable ignition - under both unexpectedly adverse conditions or if encountering a hard primer - then a smith or a DIY spring change are ways available to owners.

Modifying mainspring rates that affect hammer force is a calculated risk, though, which is why most agencies prohibit spring replacement or modification (clipping springs) in duty guns.
 
The CHP smith in the other thread does a good job of explaining the potential dangers of improperly grinding (spinning) the mainspring to reduce wire gauge and weaken spring.

And yet, he's done it on duty pistols. ;)

Modifying mainspring rates that affect hammer force is a calculated risk, though, which is why most agencies prohibit spring replacement or modification (clipping springs) in duty guns.

I agree.
I've never done it or recommended it.

But I though Doc might find it informative.

John
 
Personally I would not drop over 2 lb in hammer spring without a properly engineered extended firing pin and reduced power firing pin spring. Unfortunately we do not have that type of aftermarket support. I keep the 20 lb factory spring in my 3rd gens and just polished the action. My CZ P-07 that I carry primary have a 18 lb hammer spring, down from 20 lb factory. But it also have CGW extended firing pin and reduced power firing pin spring that's been tested for like 100k rounds to ensure reliability.

If you do start experimenting with different mainsprings, do test them with the primer you intend to carry. CCI primer used in Gold Dots are one of the hardest primer, while HST uses Federal primer which is one of the softest. Russian steel case primers are absurdly hard and inconsistent, which makes them a good primer tester. Speer Lawman have CCI primers if you don't want to mess with steel cased ammo.

On a side note, these 3rd gen's firing pins are very easy to disassemble. There is no roll pin to drive out, all you have to do is remove the safety. Check the firing pin/channel every once a while is a good idea.
 
I just received a 17 # reduced power hammer spring from numrich.
Using the new spring the DA trigger pull weight was only reduced 6 oz. Sa 4oz.

Just curious, what were the actual readings, not the differences.

What brand was the hammer spring you got from Numrich?

I only use Wolff Gunsprings when I replace the springs on a 3rd Gen pistol I buy.

Sounds like you have a digital trigger gauge. Mine's analog & doesn't go over 8# so I've never been able to know what difference a spring made to the DA pull, only how it felt "different" to me.

But as far as the SA pull goes, my notes from when I refreshed the 4506 I bought shows a Wolff 18# mainspring gave a 6.5# SA pull & a 22# mainspring gave 7.5#. Deduction would tell you a 20# spring would give a 7# SA pull, which many of my 3rd Gens have.

Frequently if I go down a few pounds on the mainspring I go up a couple on the recoil to try & keep the slide speed about the same.

Depending on it's use, some of mine are kept at 20#, some 19# & others I use a 17# mainsprings.

I reload & use CCI primers exclusively & do not have ignition troubles in any of them. The only time I got a couple light strikes, in my 1006 which didn't fire, was found to be from metal shavings that got in the firing pin's tunnel. Once thoroughly cleaned it was back to firing reliably.

I'd suggest you get a reduced power hammer spring pack from Wolff, along with a 20#, and start from a known good to see what difference you get if it really matters to you. Otherwise it seems you're trying to compare two relatively unknowns.

.
 
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And yet, he's done it on duty pistols. ;)

...

This is one of those things that an agency's head armorer (or gunsmith) can decide to take it upon themselves to approve, with the conditional approval of higher ups, of course. ;)

The former head armorer I initially worked under at my agency built PPC revolvers and made some very nice 1911's and the occasional High Power that included quite a bit of "non-factory" modifications. He was also a machinist before entering LE and a PPC shooter back in the day. He could work on both S&W and Colt revolvers, too. (We issued S&W and Colt Pythons at different times.) He was also the guy who was able to authorize the use of non-factory parts and modifications done to both duty guns and personally-owned guns (carried off-duty). Broad and willing shoulders.

After I'd started attending armorer classes - and he'd spent a lot of time standing beside me and looking over my shoulder, adding to my classroom training ;) - he eventually approved and authorized me to do some judicious spring replacements and some "smoothing" off the occasional issued guns - selectively, and as approved by him, to his standards, including some personally owned/carried guns.

Obviously, he bore the ultimate responsibility for anything done outside of "factory authorized" parts and work, and he was very careful on allowing his armorers to do such things.

It was pretty standard in armorer classes for armorers to be taught how to recognize unapproved modifications that might be done to agency weapons by individual issued users. Spring clipping was the most common thing to check for someone having done "on their own".

The usual liability concern was that someone might modify a service gun without approval and end up having the modification be the cause of a duty gun not working when desperately. Of course, right? And most especially if it resulted in someone being injured or killed when the gun didn't work as intended. Cop user or a member of the public.

Someone wanting to change to different sights or grips was normally approved, but it still had to be either done by one of the armorers, or by an "approved" outside gunsmith (on a case-by-case basis) but there were more smiths available locally back then.

Then, the growth of custom companies complicated things a little bit, like if someone brought in a personally-owned gun returned from some "custom work" and it didn't pass inspection (or wouldn't reliably function) then it wouldn't be approved for use. If it was a personally-owned gun the owner was out the cost of having it restored to normal function and could carry some other approved personal gun until it was repaired. As you might imagine, approving such work done to an agency-owned gun might be a little trickier (and cost the issued user more money to restore the agency's property).

Modifications to duty weapons that ended up compromising normal operation (or actually damaging them) could also risk a situation where a gun company tech or smith might end up being called upon to examine it, and then disavow the work done because it didn't conform to factory specs as it was produced and shipped. Think, "Hey, that's not how we designed it or built it, so it's YOUR problem."

If an injury or death was involved, the liability noose could tighten, and admin/exec folks might start looking for someone to be without a chair when the music stopped. :eek:

I remember when some of the older hands at S&W would tell how they used to clip springs to give private owners a "lighter trigger", but it was easier to teach armorers to just stay with factory spec parts and approved repairs. After all, most armorers are just armorers, not trained gunsmiths, although there are armorers working for agencies who are also trained gunsmiths. I've met a few of them. I'm NOT one of them.

Another way to get caught by surprise is for someone to come back from some training class at an outside agency (or school) ... and casually mention that an armorer at the other agency had made some modification to their an agency-owned gun, which had coincidentally come back with a functioning problem that hadn't been present before they'd let the other agency armorer "work" on the gun. One time when that happened with one of our plastic-framed pistols, it turned out the other armorer wasn't even trained or familiar with that make/model gun, but had tried to apply their armorer training on one make/model to a different make/model. As a favor, of course.

I was occasionally called and asked to help another agency's armorer with a problem, or to repair a gun owned by another agency who didn't currently have an armorer. I always made sure that my boss not only knew of (received) the request, but had authorized and directed me to perform it for the outside agency as a courtesy ... and that it was a make/model I was trained and authorized to support and repair. Liability, and taking the steps to reduce needless exposure to unnecessary liability.

I always made sure that I had approval to repair personally-owned guns, too. Most of the time I had the person requesting the repair or modification submit the request above me, and then I'd be directed to perform the authorized work.

The last thing you'd hope any armorer would ever want to do is find themselves in the position of having to explain why some "custom modification" had ended up compromising the reliability and functioning of someone's gun when they desperately needed it to work ... meaning making that explanation to the surviving widow of the user.

Naturally, I used being trained to support and repair some different makes/models of popular firearms as justification to being sent to a growing number of armorer classes and recerts over the years. (The unspoken flip side of that coin was that I wanted to be able to continue to support and repair my guns once I retired, without having to find some local smith to do simple field repairs. :) )

A man's got to know his limitations, right? And if he's smart, to stay within them.

Did I mention that I'm NOT a gunsmith, but just an armorer for some guns? ;)
 
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Personally I would not drop over 2 lb in hammer spring without a properly engineered extended firing pin and reduced power firing pin spring. ...

Consider the possibility of a reduced power FP spring to slow the retraction of the FP, and that might lead to a condition where unwanted "pin wipe" might occur.

Or perhaps a situation where a fouled FP channel might be too much for the lighter spring to even retract the FP. (Think heavy accumulated sludge and/or accumulated metal shavings from either primer cups or case rims.)

A stuck FP protruding from the breech face can bring headaches of its own.

I've sometimes used extra power FP springs in a particular gun (1911's), but have never been tempted to use a clipped or lighter power FP spring in my 3rd gens.

When you start changing spring rates, you start changing things from how a gun has been designed and tested.

Here Be Dragons, that used to be seen in the borders of unknown areas on old maps, comes to mind. :D

This is where engineers and experienced gunsmiths familiar with particular designs can be very helpful. Not only in achieving something, but in helping someone avoid problems of which they may be unaware.
 
CZ is blessed with aftermarket support from CGW. CZ's own gunsmiths speaks highly of their aftermarket products and acknowledge the improvements they've made over factory parts. I certainly trust their products as they are very specialized in CZ guns. I certainly wouldn't trust spring kits from eBay specials, or even Wolff who simply just produces spring to a certain spec for people to experiment with.

Support for 3rd gen pretty much was never there to begin with. There are a few good gunsmiths that specialize in them, but they can't really design, produce, and test parts. These Smith's for the most part should be left as close to factory spec as possible if intended for carrying.

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Hi, Doc1500

If I haven't said it yet, Welcome to the Forum!

Re: Reduced power Main (hammer) springs for CHP4006TSW models, there is a Forum member whose handle is: adrianolsen.

He reports that he is a CHP Gunsmith.

In posts #36-#39 of this attached thread: http://smith-wessonforum.com/smith-...9-anybody-have-chp-4006-a.html?highlight=spin he speaks to your issue.

From what I understand, you may not have a "standard" main spring in your pistol. ;)

John
This is exactly what I was wondering, if the guns are made exclusive for CHP and s&w did change the Springs to lighter 17 -18 pound for CHP, it probably would not be mentioned or even suggested for regular consumer only CHP Smiths would know.
If S&W did do this for CHP then I'm sure they did testing to make sure it was reliable before they put it out the door.
I don't know I'm just thinking here throwing stuff up against the wall.
All you guys are terrific here with all your suggestions and knowledge, keep it up and loving it.
Edit: the 17 lb spring I received is a wolf spring.
Here is the spring info
2guh83s.jpg
 
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Just curious, what were the actual readings, not the differences.

What brand was the hammer spring ?

.
Wolff spring.
Trigger pull out of the box recieved
DA 11.6#-SA 6.10#
After polishing: DA 10.9#- SA 6.2#.
After installing the wolf 17# spring, DA 10.3# SA 5.14.
 
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