Current J Frame production

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There are many conflicting views on the infonet concerning current J Frames trigger components, MIM parts contained within and machining or polishing of these parts.
Which components are MIM and are these components through hardened?
Which components are not MIM and and are they through hardened or case hardened?
Are there any components that S&W says absolutely do not polish or stone?

[Chuck Haggard]

All of the current J frames have MIM internals. The guys I know that are old school S&W smiths and able to go awesome trigger work on the older guns won't touch the new guns with MIM parts.

That said, I've found that the newer guns smooth out rather quickly with dry and live fire.

[Trajan]

Interestingly enough, new 442s and 642s, at least the no lock variants, have single action notches on the hammer.

Why? Because Smith and Wesson.

[UNK]

I can't attest to the validity of this letter, if valid I find it very interesting.

I have read with much interest the many comments in this [Smith and Wesson] forum pertaining to MIM, MIM Parts and the use of same in a S&W product. So far I have come away with several impressions and they are, "people in general don't like/trust MIM parts", and, "no one has said why." I will take a stab at this issue and see where it goes.

As background to our decision to use MIM in some areas of our Mfg Process we took a long hard look at our "Life Time Service Policy". It was clear to us that any change in any of our products such as the use of MIM components had to show equivalent or better performance and durability to those components that were being replaced or the "Lifetime Service" would haunt us forever. The second consideration was to determine if the change was too radical a departure from S&W mainstream design.

For the performance and durability issues we decided that if MIM could be used for the fabrication of revolver hammers and triggers successfully this would truly be an "Acid Test". There is nothing more important to a revolvers feel than the all-important Single Action that is established between the hammer and the trigger. Mechanically few places in a revolver work harder than at the point where the hammer and trigger bear against each other. If these surfaces wear or lose their edge the "feel" is lost. Initial testing was on these two critical parts.

Over time we arrived at a point where our best shooters could not tell the difference between a revolver with the old-style hammer and trigger and the new MIM components. Special attention was given to their endurance when used in our very light magnum J-frames such as the early prototype 340 & 360 Sc's. None of our revolvers work their components harder than these small magnum revolvers. Throughout this testing MIM held strong and finally we determined that this change judged on the basis of durability and feel was a good one.

The second area of concern to S&W was our customer’s reaction to this departure from the traditional. Many heated, intense discussions resulted but in the end the decision was made to move ahead with MIM. The issue of cost was only one of the considerations in making this decision. Equally as important was the issue of part-to-part uniformity and the result of this of course is revolver-to-revolver consistency. We found that revolvers that used MIM hammers and triggers required almost no fitter intervention in those areas during final assembly and final inspection and trigger-pull monitor rejection rates dropped markedly on finished guns. From an internal process point of view it appeared a "Winner".

Let's shift gears for a moment and talk about the MIM process. It is unclear to me as to the reason for many of the negative feelings on the forum concerning MIM. Typically when people complain and aren't specific in the reason why, the problem is often created by a departure from the "Traditional". Perhaps that is indeed what is bothering some people when they view MIM.

The term MIM stands for Metal Injection Molding. It holds some similarities to Plastic Injection Molding and many differences as well. To start we would take a finally divided metal powder. This could be stainless or carbon steel. Today even titanium is being used in some MIM fabrications. We would mix the metal powder and a thermoplastic binder (generally a wax) forming slurry of sorts when heated and inject this mix into a precision mold and finally form what is known as a “green part". This part is roughly 30% larger than the finished part it will become at the end of the process. Interestingly enough the green part at this stage can be snapped in two with simple finger pressure. The green parts are then placed in a sintering furnace filled with dry hydrogen gas and the temperature is brought almost to the melting point of the metal being used. Over time the wax in the green part is evaporated, the metal fuses and the part shrinks 30% to it's final correct dimensions. At this stage of the process the MIM part has developed 98 to 99%of the density of the older wrought materials and a metallurgy that is almost identical. Dimensionally it is finished and no machining is required. However the job is not yet done and the MIM parts are brought to our heat treat facility for hardening and in the case of hammers and triggers, case hardening. Depending on the particular metal alloy that was used at the start of the process we apply a heat treat process that is the same as would be used if the material were the older wrought style. Final hardness, case thickness and core hardness are for the most part identical to parts manufactured the older way.

Lets look for a moment at how we achieve dimensional precision when comparing these 2 processes. The old parts were each machined from either bar stock or a forging. Each cut and every resulting dimension was subject to machine variations, cutter wear, operator variations etc. If every operation was done exactly right each and every time and the cutter didn't let you down you would have produced a good part but sometimes this didn’t happen, resulting in a rejected gun and rework or in the worst case an unhappy customer. With MIM parts you must still machine to very high tolerances and your cutters have to be perfect and your machinist has to be highly qualified but all of this only has to come together one time. That time is when the injection mold is made. Typically a mold for this process costs S&W between $30,000.00 and $50,000.00; once it is perfect every part it makes mirrors this perfection and you have, in my view, a wonderful manufacturing process.

Hopefully this description will help us all better understand the MIM process. Please forgive the spelling errors and misplaced punctuation. I have no spell checker on this and the phone continues to ring!

Have a Great Weekend,

Herb [Belin,
Project Manager, Smith & Wesson]


Additional Point:

Currently S&W is paying about $1.20/Lb for stainless steel bar stock. Raw MIM stainless steel inject able material costs $10.00/Lb.

[UNK]

Is it worthwhile to polish contact points? I'm talking micron paste polishing not stone polishing. What is the consensus on long term reliability of the spring kits being offered now? I have seen the Apex kit which has a replacement firing pin being mentioned favorably.
I am hesitant to replace stock springs with a spring of a different weight. My thought process is to polish first then see the results before going further..

All of the current J frames have MIM internals. The guys I know that are old school S&W smiths and able to go awesome trigger work on the older guns won't touch the new guns with MIM parts.That said, I've found that the newer guns smooth out rather quickly with dry and live fire.

[RoyGBiv]

Additional Point:

Currently S&W is paying about $1.20/Lb for stainless steel bar stock. Raw MIM stainless steel inject able material costs $10.00/Lb.
Clarifying point:
Although bar stock is cheaper than MIM raw material (powder), MIM requires a smaller investment in machine time and labor to make a finished part. As was discussed in the letter above, the machine time, labor and QC variables in producing parts from bar stock is greater than the cost of materials difference.

[UNK]

Clarifying point:
Although bar stock is cheaper than MIM raw material (powder), MIM requires a smaller investment in machine time and labor to make a finished part. As was discussed in the letter above, the machine time, labor and QC variables in producing parts from bar stock is greater than the cost of materials difference.

Yes I didn't know that but because of the wording I didn't expect that statement to be the whole story.

[Chuck Haggard]

No bullshit, I find buying snap caps and dry firing the crap out of the gun to be the best "polish" for the new MIM part J frames I have tried out.

[UNK]

OK I'll stop and get some on the way home from work today.
What about spring kits or apex kit to reduce lb. of pull. Good idea or not?
And one last question, I have read that the new barrels are not lead friendly because of the way the lands are cut. I have read that heavy fouling occurs in as little as 60 rounds. Does anyone have experience with this?


No bullshit, I find buying snap caps and dry firing the crap out of the gun to be the best "polish" for the new MIM part J frames I have tried out.

[Chuck Haggard]

I haven't done the Apex kits on any of my guns, guys like Claude report that they do improve the trigger and lighten the pull.

[LSP972]

And one last question, I have read that the new barrels are not lead friendly because of the way the lands are cut. I have read that heavy fouling occurs in as little as 60 rounds.

Not in my experience, with a sample of one M-360PD.

Keep in mind that the term "heavy fouling" means different things to different people... and even more pertinent, bullet composition has more of a bearing on barrel/cylinder leading than ANY other factor (assuming proper caliber bullets are used in a particular firearm, etc.).

IOW, current Remington 158gr lead SWC bullets will probably show more leading than Winchester or Federal, as Remington has pretty consistently used a softer bullet alloy... for many, many years.

Then you have bullets cast by reloaders. A meticulous reloader/bullet caster will ensure that his metal has the proper mixture of lead, tin, and antimony. The guy who gets buckets of wheel weights from Bubba's Tire and Donut Shoppe, dumps them in the crawfish burner, and gets MOST of the dross when he skims the clips out... well, let's say his metal composition can be questionable (i.e., soft). And that's assuming the bullets are sized properly for your gun. A combination of soft metal and a couple of thousandths over size can clog up a forcing cone faster than a cat can... well, quickly.

So, as with most things, the answer to your question is... it depends.

That said... I have run the gamut of lead bullets (from high quality commercial offerings to some of those Bubba bullets) through my 360PD; right at 5K worth. The ones I expected to cause leading- the Bubba bullets- caused leading. The "good stuff" didn't. BTW, my definition of heavy leading is when I have to get the special tools- i.e., Lewis Lead Remover- out to clean the revolver properly.

And my opinion of MIM parts-again, with a sample of one- echoes what Chuck has heard. They smooth right up with a lot of use. In my case, shooting the gun a lot.

.

[UNK]

OK Thanks I appreciate the info. I do believe you have quite a bit of experience as a revolver armorer and I was hoping you would weigh in.
What are your thoughts on changing springs for a lighter pull. There are spring kits available from a variety of sources, and then there are the APEX kits. I've taken a J frame to a gunsmith for a much improved trigger but honestly I don't know exactly was done. I also don't know about the long term effects of the trigger job because I sold it but I never had any problems while I had it.


Not in my experience, with a sample of one M-360PD.

Keep in mind that the term "heavy fouling" means different things to different people... and even more pertinent, bullet composition has more of a bearing on barrel/cylinder leading than ANY other factor (assuming proper caliber bullets are used in a particular firearm, etc.).

IOW, current Remington 158gr lead SWC bullets will probably show more leading than Winchester or Federal, as Remington has pretty consistently used a softer bullet alloy... for many, many years.

Then you have bullets cast by reloaders. A meticulous reloader/bullet caster will ensure that his metal has the proper mixture of lead, tin, and antimony. The guy who gets buckets of wheel weights from Bubba's Tire and Donut Shoppe, dumps them in the crawfish burner, and gets MOST of the dross when he skims the clips out... well, let's say his metal composition can be questionable (i.e., soft). And that's assuming the bullets are sized properly for your gun. A combination of soft metal and a couple of thousandths over size can clog up a forcing cone faster than a cat can... well, quickly.

So, as with most things, the answer to your question is... it depends.

That said... I have run the gamut of lead bullets (from high quality commercial offerings to some of those Bubba bullets) through my 360PD; right at 5K worth. The ones I expected to cause leading- the Bubba bullets- caused leading. The "good stuff" didn't. BTW, my definition of heavy leading is when I have to get the special tools- i.e., Lewis Lead Remover- out to clean the revolver properly.

And my opinion of MIM parts-again, with a sample of one- echoes what Chuck has heard. They smooth right up with a lot of use. In my case, shooting the gun a lot.

.

[LSP972]

What are your thoughts on changing springs for a lighter pull.

Basically, a two-edged sword. Its definitely doable, but the doer needs to KNOW what he is about or bad things can happen.

There are two springs which control pull weight; the main spring, and the trigger rebound spring. The former is VERY difficult to "work" without gooning something up, and is best left alone. J frames use a coil mainspring, which is more complex than the leaf spring the larger revolvers employ. A leaf mainspring can actually be worked, albeit carefully, by thinning the sides slightly, or a strategically located bend. Not so the coil type. Anyway, the trigger rebound srping is what most folks attack; either by clipping coils or replacing with a "kit".

I have installed a half-dozen or so of the Apex kits in Centennial J frames. They work fine, and do lessen the pull somewhat; by how much depends on the condition of the hammer and trigger mating surfaces, the frame bosses those parts ride on, and the timing (hand-to-ratchet fit). I have no experience with any other Apex stuff, but they seem to have a handle on it so I would not hesitate to try whatever else they may have for "regular" DA/SA revolvers. A lighter rebound spring couldn't hurt… up to a point.

The problem with a lighter rebound spring is, if you hit the threshold of trigger return energy you have now made your revolver into a sometimes-shooter. A certain amount of energy is needed to get that trigger back forward. Make it too light, and the cylinder can "skip" in rapid fire (AKA "throw-by"). Worst case, the trigger won't go back fully forward without a manual push. Bad juju.

Most everybody seems to think (because they read it over and over again in gun magazines and the internet) that DA revolvers are simple beasts; much simpler than semi-autos. Wrong. Revolver parts move back and forth, up and down, and around and around… all at the same time. Disturb that delicate balance (as most table-top "trigger jobs" do), and you've got trouble. Generally, when you change one thing on a DA revolver, you must adjust another thing to maintain that balance. A good example is the Apex Centennial spring kit; in addition to the lighter trigger rebound spring, you also get a new firing pin and firing pin spring. Both of the latter are necessary to ensure reliable ignition with the lightened DA pull (no SA capability on these guns).

It would be unethical of me to describe methods of lightening trigger pulls using existing parts. What I know, I learned from working on hundreds of the things; and that sort of knowledge is NOT taught in armorer classes. I have a pretty good idea of how far to go, I have the tools and gauges to CHECK how far I've gone, and parts if I go too far and have to start over. Plus, the current MIM parts are NOT the "same" (property-wise; they look the same and work the same, though) as the forged/milled parts I know so well, so I'd be talking out of my ass in any event if the topic is a post-90s gun.

Here's the best advice I can give you. We're talking J frames here; they are for shooting people when the shooter is under high duress. They are not target guns; in fact, if you enjoy shooting a lightweight example for an extended session, then you are more man than me. With that in mind, the smart move is to live with the trigger that the revolver came with. It passed the gauging and reliability tests at the plant (usually); and as we all know, reliability is the number one factor in a defensive firearm; it MUST go bang when you need it to.

As others here have noted, you can smooth up the action a bit by extensive dry firing. My M-360PD, purchased in 2002 and having had in excess of 5K rounds through it, is every bit as smooth and crisp as the 1966-vintage M-37 I worked long and hard over. The only fiddling I did with that piece was to remove the lock mechanism improperly; but that has been covered elsewhere on this forum. My point here is, after the first thousand rounds or so the action improved noticeably. Live firing accelerates the process a bit, because the recoil actually helps "marry" the working parts to each other. Dry firing will do this as well… it just takes longer.

If you simply cannot keep yourself from tinkering, I can recommend the Apex kit for a Centennial J frame. I'm talking about the enclosed hammer model. AFAIK, all J frames made after 1996 or so have frame-mounted inertial firing pins. Whether or not the firing pin and spring included in Apex kit for the 442/642/et. al. will fit an exposed-hammer example, I do not know. A call to Apex would answer that question.

Any other "kit" offerings, etc., I would be leery of. S&W did, for many years, offer a lighter trigger rebound spring for K frames. Made expressly for the single-action-only version of the K-38, a dedicated target piece, it was (and is) a limited item, highly sought after by mechanics doing PPC trigger jobs. I know of no such goodies ever made by them for J frames.

Sorry for the novella, but this is a complex situation that has no easy answers.

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[UNK]

Simply awesome answer. Thanks for your time and sharing of your knowledge.

Basically, a two-edged sword. Its definitely doable, but the doer needs to KNOW what he is about or bad things can happen.

There are two springs which control pull weight; the main spring, and the trigger rebound spring. The former is VERY difficult to "work" without gooning something up, and is best left alone. J frames use a coil mainspring, which is more complex than the leaf spring the larger revolvers employ. A leaf mainspring can actually be worked, albeit carefully, by thinning the sides slightly, or a strategically located bend. Not so the coil type. Anyway, the trigger rebound srping is what most folks attack; either by clipping coils or replacing with a "kit".

I have installed a half-dozen or so of the Apex kits in Centennial J frames. They work fine, and do lessen the pull somewhat; by how much depends on the condition of the hammer and trigger mating surfaces, the frame bosses those parts ride on, and the timing (hand-to-ratchet fit). I have no experience with any other Apex stuff, but they seem to have a handle on it so I would not hesitate to try whatever else they may have for "regular" DA/SA revolvers. A lighter rebound spring couldn't hurt… up to a point.

The problem with a lighter rebound spring is, if you hit the threshold of trigger return energy you have now made your revolver into a sometimes-shooter. A certain amount of energy is needed to get that trigger back forward. Make it too light, and the cylinder can "skip" in rapid fire (AKA "throw-by"). Worst case, the trigger won't go back fully forward without a manual push. Bad juju.

Most everybody seems to think (because they read it over and over again in gun magazines and the internet) that DA revolvers are simple beasts; much simpler than semi-autos. Wrong. Revolver parts move back and forth, up and down, and around and around… all at the same time. Disturb that delicate balance (as most table-top "trigger jobs" do), and you've got trouble. Generally, when you change one thing on a DA revolver, you must adjust another thing to maintain that balance. A good example is the Apex Centennial spring kit; in addition to the lighter trigger rebound spring, you also get a new firing pin and firing pin spring. Both of the latter are necessary to ensure reliable ignition with the lightened DA pull (no SA capability on these guns).

It would be unethical of me to describe methods of lightening trigger pulls using existing parts. What I know, I learned from working on hundreds of the things; and that sort of knowledge is NOT taught in armorer classes. I have a pretty good idea of how far to go, I have the tools and gauges to CHECK how far I've gone, and parts if I go too far and have to start over. Plus, the current MIM parts are NOT the "same" (property-wise; they look the same and work the same, though) as the forged/milled parts I know so well, so I'd be talking out of my ass in any event if the topic is a post-90s gun.

Here's the best advice I can give you. We're talking J frames here; they are for shooting people when the shooter is under high duress. They are not target guns; in fact, if you enjoy shooting a lightweight example for an extended session, then you are more man than me. With that in mind, the smart move is to live with the trigger that the revolver came with. It passed the gauging and reliability tests at the plant (usually); and as we all know, reliability is the number one factor in a defensive firearm; it MUST go bang when you need it to.

As others here have noted, you can smooth up the action a bit by extensive dry firing. My M-360PD, purchased in 2002 and having had in excess of 5K rounds through it, is every bit as smooth and crisp as the 1966-vintage M-37 I worked long and hard over. The only fiddling I did with that piece was to remove the lock mechanism improperly; but that has been covered elsewhere on this forum. My point here is, after the first thousand rounds or so the action improved noticeably. Live firing accelerates the process a bit, because the recoil actually helps "marry" the working parts to each other. Dry firing will do this as well… it just takes longer.

If you simply cannot keep yourself from tinkering, I can recommend the Apex kit for a Centennial J frame. I'm talking about the enclosed hammer model. AFAIK, all J frames made after 1996 or so have frame-mounted inertial firing pins. Whether or not the firing pin and spring included in Apex kit for the 442/642/et. al. will fit an exposed-hammer example, I do not know. A call to Apex would answer that question.

Any other "kit" offerings, etc., I would be leery of. S&W did, for many years, offer a lighter trigger rebound spring for K frames. Made expressly for the single-action-only version of the K-38, a dedicated target piece, it was (and is) a limited item, highly sought after by mechanics doing PPC trigger jobs. I know of no such goodies ever made by them for J frames.

Sorry for the novella, but this is a complex situation that has no easy answers.

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[UNK]

I talked with a gunsmith yesterday. His opinion was that current J Frames are good to go. He said for those with a weaker grip or who are unable to manage the trigger pull he recommends cutting two coils off the trigger return spring. He said if you have good return you can cut another 1/2 coil. He also said it is the same thing S&W will do if you send it back to the performance center His opinion is the same as yours and LSP972 if its not rough and catchy just shoot and dry fire it. This seems like the most reliable way to go if you are going to do anything besides shoot/dry fire.


I haven't done the Apex kits on any of my guns, guys like Claude report that they do improve the trigger and lighten the pull.


No bullshit, I find buying snap caps and dry firing the crap out of the gun to be the best "polish" for the new MIM part J frames I have tried out.

[LSP972]

He also said it is the same thing S&W will do if you send it back to the performance center.

This is my skeptical face.

I wish I could find that "Bullshit Meter" thingie.

Clipping coils on a "serious use" S&W revolver is... just... retarded.

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[UNK]

This is my bowing in respect to your experience face. I am not being argumentative. I enjoy having a conversation and learning. And I am not saying that I will do anything other than what you recommended.
The gunsmith told me the trigger return spring is an 18 pound spring. I have seen that Jody reported that trigger return was too weak with the APEX kit. Also as I understand, the APEX changes the mainspring, the firing pin, the firing pin spring and the trigger return spring.
I'll say this, I just put a Crimson Trace LG405 laser on it and in dry fire it's not hard to control as is. I still need to stop by and get a case of ammo and snap caps. Holster should be here in a couple of weeks so I'm not in a hurry.


This is my skeptical face.

I wish I could find that "Bullshit Meter" thingie.

Clipping coils on a "serious use" S&W revolver is... just... retarded.

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[TMC1926]

I own my own gunsmithing business and have been professionally gunsmithing for 20 years now. I do lots of revolver work. I prefer the MIM parts over the forged parts. I find the consistency and fit , finish, and function to be greater with the MIM parts. I am able to achieve better trigger jobs with these parts. I have even had customers send guns in for unrelated warranty work to S&W that I have done trigger work to. The guns were returned with the same parts still installed. If S&W finds parts worked on that does not meet factory specification they replace the parts. I've also spoke with numerous reps and customer service employees who have stated it is fine to polish the parts if you know what your doing and do proper work. I still love the forged parts but there is a real difference in a Monday morning gun and a Friday afternoon gun when the guns were hand fit which makes consistent work more strenuous. I hope this helps.

[Chuck Haggard]

I know a number of people that have bought the spring kits from Wolfe and played around with the various weights until they had a trigger they like AND reliable ignition and trigger return.

Cutting coils is indeed a bad idea IMHO


I do find that the guns are smoothed up rather nicely nine times out of ten, and either the trigger is lighter or my trigger finger is stronger, if one just does the work and dry fires the gun a lot.

[UNK]

Thanks for your input. Earlier in the thread (page 1) I posted a letter from an individual at S&W who basically said the same thing.


I own my own gunsmithing business and have been professionally gunsmithing for 20 years now. I do lots of revolver work. I prefer the MIM parts over the forged parts. I find the consistency and fit , finish, and function to be greater with the MIM parts. I am able to achieve better trigger jobs with these parts. I have even had customers send guns in for unrelated warranty work to S&W that I have done trigger work to. The guns were returned with the same parts still installed. If S&W finds parts worked on that does not meet factory specification they replace the parts. I've also spoke with numerous reps and customer service employees who have stated it is fine to polish the parts if you know what your doing and do proper work. I still love the forged parts but there is a real difference in a Monday morning gun and a Friday afternoon gun when the guns were hand fit which makes consistent work more strenuous. I hope this helps.

[Beat Trash]

I'm not qualified to work over a S&W revolver action. But many years ago, I used to shoot on our county Police Association's pistol team competing with S&W revolvers. Back then I spent a lot of time looking over the shoulder of various armors with decades of experience tuning S&W revolvers, trying to learn. I learned a lot about how those guys would work over a S&W action.

LSP972 and Chuck both are giving great advice. I remember some older "tricks" that were done to competition guns, that the smith's said they would not do to a duty gun. Cutting coils off of a a main spring would be one example. Going with lighter main springs, or contouring flat mainsprings would be another.

I installed an Apex kit into a new J-frame 642 that has MIM parts in it. While it did lighten the trigger pull some, I'm tempted to pull the Apex kit out and return the gun to stock. I've test fired the gun with the Apex kit and haven't had issues. But I think that I would feel better with the gun in a stock configuration.

When the gun was brand new, I locked up the live rounds, loaded the gun with some snap caps, and sat in front of the TV and dry fired it for a while. Smoothed out the trigger pull. For the intended usage of a J-frame 642, I can live with a trigger pull that is a couple of pounds heavier, so long as it's smooth.

[UNK]

LSP972 and Chuck both are giving great advice. I remember some older "tricks" that were done to competition guns, that the smith's said they would not do to a duty gun. Cutting coils off of a a main spring would be one example.

I absolutely agree, both of these guys have tons of experience and I am paying attention. The statement in question doesn't have to do with mainsprings. It has to do with only the trigger return spring.
Cutting springs is a no go...I got it.
I have read of people who have installed a trigger return spring with a different weight with good results. The lightest weight I have seen mentioned is 13 lbs. This would leave everything else in the revolver stock.
This is a theoretical inquiry, primarily with the point of learning about the J frame trigger, because at this point I am not planning on doing anything.

[LSP972]

I am not being argumentative..

No worries, I didn't think you were.

The problem here is that anyone can call himself a "gunsmith". To my knowledge, S&W has NEVER offered armorer training to anyone but verified LE people and a few scattered non-LE folks who worked/work at authorized service centers. Besides, all their basic-level armorer schools do is teach how the parts fit together and interact, how to strap up a cylinder; basically, how to build one. Where you learn how to diagnose problems and fix them, plus tune-up tips, is at the advanced course (offered only at the factory, AFAIK), and by working on a bunch of them.

I'm not pointing a finger at anybody specific, but just sayin'...

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[LSP972]

I find the consistency and fit , finish, and function to be greater with the MIM parts. .

That's what Herb Belin claimed, when the MIM parts first began wide-spread integration into their revolvers and pistols.

What they (S&W) DON'T tell you is the decision to use MIM was reached after a lot of soul-searching and number crunching. Their work force was approaching a sea change; most all of the long-time, highly experienced machinists, tool makers, and fitters were looking at retirement. S&W had the choice of hiring, training, and paying (at ruinous rates; while never a "union shop", the new breed of folks were demanding union pay scales) a lot of new employees. The move to MIM reduced the need for many of these folks (except fitters), so it made for a better bottom line.

I have been told that the main advantage of MIM parts is that they are through-hardened. The old forged, case-hardened parts you had to be damned careful with; break through that case hardening with file or stone, and the part was ruined. A part that is the same hardness all the way through would definitely make whittling on trigger/hammer steps a bit less daunting, for sure.

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[UNK]

This is from Herbs letter I posted earlier.... However the job is not yet done and the MIM parts are brought to our heat treat facility for hardening and in the case of hammers and triggers, case hardening. Depending on the particular metal alloy that was used at the start of the process we apply a heat treat process that is the same as would be used if the material were the older wrought style. Final hardness, case thickness and core hardness are for the most part identical to parts manufactured the older way.


That's what Herb Belin claimed, when the MIM parts first began wide-spread integration into their revolvers and pistols.

What they (S&W) DON'T tell you is the decision to use MIM was reached after a lot of soul-searching and number crunching. Their work force was approaching a sea change; most all of the long-time, highly experienced machinists, tool makers, and fitters were looking at retirement. S&W had the choice of hiring, training, and paying (at ruinous rates; while never a "union shop", the new breed of folks were demanding union pay scales) a lot of new employees. The move to MIM reduced the need for many of these folks (except fitters), so it made for a better bottom line.

I have been told that the main advantage of MIM parts is that they are through-hardened. The old forged, case-hardened parts you had to be damned careful with; break through that case hardening with file or stone, and the part was ruined. A part that is the same hardness all the way through would definitely make whittling on trigger/hammer steps a bit less daunting, for sure.

.

[LSP972]

The way it was explained to me, the parts come out of the final heat-treat process as ready-to-use; IOW, very little, if any, final machining to bring the part into spec.

Again, that's hearsay. All I know for sure is, the MIM parts in my example of one work fine and have held up to moderate use. I did whack the spur off of the hammer early on, with absolutely no ill effects.

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What are your choices for ammo?
The way it was explained to me, the parts come out of the final heat-treat process as ready-to-use; IOW, very little, if any, final machining to bring the part into spec.

Again, that's hearsay. All I know for sure is, the MIM parts in my example of one work fine and have held up to moderate use. I did whack the spur off of the hammer early on, with absolutely no ill effects.

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[LSP972]

What are your choices for ammo?

Speer Gold Dot 135gr +P "short barrel", or Remington 158gr LSWCHP +P (Remington because their alloy has been classically softer, offering more chance for expansion), or Winchester/Federal's version of the "FBI load" (which is the Remington load just described).

Lacking those, good old 148gr lead wadcutters.

For a practice round, I load "bunny farts" with four grains of N320 under either a 110gr JHP or 135gr cast Bayou Bullet. Much easier on my old wrists...

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Thanks again for all the info. You have cleared up a lot of misconceptions for me.

Speer Gold Dot 135gr +P "short barrel", or Remington 158gr LSWCHP +P (Remington because their alloy has been classically softer, offering more chance for expansion), or Winchester/Federal's version of the "FBI load" (which is the Remington load just described).

Lacking those, good old 148gr lead wadcutters.

For a practice round, I load "bunny farts" with four grains of N320 under either a 110gr JHP or 135gr cast Bayou Bullet. Much easier on my old wrists...

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[LSP972]

Glad to be of help.

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[Chuck Haggard]

You might want to read Doc's bit on back-up guns in the ammunition forum, it's a sticky, and the thread ref wadcutters from snubs, also in the ammo section.

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I will thank you

You might want to read Doc's bit on back-up guns in the ammunition forum, it's a sticky, and the thread ref wadcutters from snubs, also in the ammo section.