Metal Injection Molding - MIM - Why The General Dislike?

[SweetMK]

I have noticed the general dislike of revolvers with MIM parts - buyers looking for guns specify no MIM.

Are the MIM parts prone to failure? Or is this just a perceived lower value part?

I opened up a 617-4 MIM revolver that I recently purchased.

I felt the parts were much better fitting than previous vintage S&W revolvers I have worked to smooth the action of.

The 617-4 may get a new spring, but, I was impressed with how smooth the gun generally functions. I always wondered how S&W got the 10 shot to "time" properly. I think S&W would have a hard time getting the finish and repeat-ability of MIM parts with machined components, especially at this price point.

I doubt they could get a 10 holer to time as correctly, without MIM. Of course, that is just MHO!!

I can not count how many 6-holers I passed up after finding during cocking the cylinder did not "lock up". This 617 10-holer does that perfectly.

Will somebody help me understand MIM value, function, and performance??

 

[photoman]

I owned a Model 625-6 for a while that had MIM guts. That one had a great action. Very smooth from the factory.

 

[Pisgah]

MIM parts don't look as nice as color casehardened parts, and some say the forged parts are easier to smooth and tune. In all other respects they are superior -- and, yes, that means they are less expensive to make, among other things. Something wrong with that? Not to me.

 

[fat tom]

I have noticed the general dislike of revolvers with MIM parts - buyers looking for guns specify no MIM.

Most of us are just anal about such things.
f.t.

 

[N4KVE]

Buyers are disappointed when they buy a gun, & it's put together with cheaper parts than it used to be. When I can lay out a bunch of Sig 226's, & you can see the German made ones from the 80's have milled parts, & the newer ones have cast, or mim parts, it means Sig wanted to save money to keep costs down. Sure the parts won't last as long, but they'll probably outlive the barrel. Arsenal AK trigger parts used to be forged. [milled] Now they're mim parts. That's why I replace my AK cast, or mim trigger parts with Chinese milled parts. Most of my pistols I fire 100 rds a year, so in my case it probably wouldn't matter, but to some, [myself included] newer isn't always better. GARY

 

[RightArm]

I think it's a general fear of technology and, therefore automation.
Haven't you seen The Terminator. One day, the computers will make all the MIM parts and guns they need to wage war on mankind.

 

[gunny4053]

Perception is everything. Forged and machined parts mean greater attention to detail and hands on care during the manufacture of fine firearms. MIM means a faster, cheaper, lazier if you will, way to manufacture a firearm. Both perceptions, whether true or not, it's the way people see it.

For many, the thought of a classic firearm being made by any other process than forging and machining parts from solid steel is sacrilegious. It's just the way we are.

That stinking hole in the side on the other hand.

 

[BCDWYO]

Personally, I don't really have a problem with the MIM parts (unlike my feelings about the IL, but that is another well-beaten dead horse). But if I were offered a MIM or a forged S&W, with all other factors being equal, I would take the forged one every time because the perceived value (and therefore future resale value) is higher with collectors.

 

[gdauth]

Someone said that newer isn't always better, true, but the implication is that it is always worse. Not true. Think about this, with their life time warranty, S&W does not want to institute a new process just because it is cheaper, if it does not result in a longer trouble free life for the product. Warranty work is expensive, very expensive. Even with modern CNC machining systems, the process is subject to errors. Tools wear, the machines wear and things change. And the idea that just because there are machining marks on a part, it doesn't mean that someone took care and gave extra effort. Computers don't care, they just follow preprogrammed instructions.

 

[bshepherd]

The only S&W revolver I have with MIM parts is a Model 57 Mountain Gun. I like it well enough. What gets me is the sound of the action. Cock it, or pull the trigger double action and it sounds like a cheap cap gun. Do the same with an earlier all forged parts action and it sounds solid. Just my perception, I like the sound and feel of the older actions much better.

 

[DonD]

Sure the parts won't last as long, but they'll probably outlive the barrel.

Show some reliably documented evidence that S&Ws MIM parts won't last as long as milled or forged. You won't because you can't. S&W wouldn't be fitting MIM parts if they weren't reliable and durable. Don

 

[wproct]

Each and every MIM equipped S&W revolver that I have owned has had just as smooth (or smoother) action as any non MIM revolver that I own. I do think that I can tell a difference in the sound of the action. I have a model 60-12 that has MIM parts but no lock, and I'm OK with that. However, like it or not, it does make a difference in the value of the revolver.

 

[jdh]

Perceptions can be warped by emotions.
Less expensive is not always lower quality.

 

[Snapping Twig]

In my case, and this is my own perception, both work - but - the specter of catastrophic failure is greater with MIM.

I realize both types fail and I realize both types are dependable, what I am saying is that the potential for a void leading to failure exists with MIM and when this happens the part crumbles, breaks, lets go.

Forged is less subject to this due to the process of manufacture, but that's not to say it can't fail.

I've had non firearm MIM failure and I recall my days of youth with metal parts of toys failing and seeing the crystalline composition inside and I can't shake that image when I think of MIM.

I know this is not germane to current MIM, but none the less it makes me shun MIM.

 

[Vern]

...
Are the MIM parts prone to failure? Or is this just a perceived lower value part?

I think that fear breakage is the underlying reason. I don't know if that fear is real or not, but a lot of 1911 guys really make a big deal of it. The purists deride the "MIMber" 1911s because Kimber is known to use MIM parts. The perception is that MIM parts are cheap and therefore unreliable.

BTW, I have a 10 shot M17 that I really like. I shoot it better DA than I do most of my SA pistols.

Vern

 

[David Sinko]

So why didn't S&W just rivet MIM firing pins into MIM hammers? Why the complete transition to frame mounted firing pins across the entire revolver lineup?

And what is the bottom line in savings per individual revolver? Is it pennies? Dollars? Tens of dollars?

Dave Sinko

 

[AveragEd]

I think the dislike comes simply from the fact that most of the MIM-haters are older guys like me and you know how much us olde pharts hate change. If it is not made the way "it used to be," it's bad.

I spent my working life in the automobile industry as a dealership master technician and then service manager. When we got the first computer-controlled fuel and ignition systems in the mid-70s, they were nightmares to diagnose - and there were plenty of problems to diagnose. But as the years passed, the manufacturers got a better handle on electronic controls and the result is the smooth, powerful yet economical engines we have today. But getting there caused a lot of gray hair!

MIM parts are being received the same way those of us in the automotive field received those electronic controls. It's new and it's different, so it sucks. But in time, it also will be accepted.

All my S&Ws are non-MIM, non-IL guns. I felt that I will always be able to buy MIM/IL guns, so I ought to get the old ones while they are still available in nice condition. I own one MIM gun, a Kimber Stainless Gold Match II in .45ACP. On that gun, I don't mind the MIM parts because they look just like the forged ones on my older 1911s. There is no hollow back on the trigger and the hammer is shaped exactly the same as a forged hammer. And there is no lock.

I guess it's a case of out of sight, out of mind. Or what I can't see can't hurt me.

Ed

 

[cass]

I don't know what percentage of MIM parts are in the Smiths, but I would not be concerned as long as those installed parts weren't parts subjected to stress or fatigue. I can live with MIM, not with the clinton hole.

 

[TheTinMan]

In my non-technical opinion, there is no fundamental problem with the metal injection molding process. It is cost effective. It works when executed correctly and used for parts that aren't stressed more than MIM can handle.

The quality control problems come in when the accountants and marketing execs get together and decide on a price point for gun X. Then they ask "How can we make the gross margin as big as humanly possible for gun X?" And they push the engineers to use as much MIM as possible and to push the envelope on how to use it, especially in terms of quality control procedures.

 

[Culina]

I don't like the MIM part because the tend to be kind of ugly externally. I like flash chromed and color case hardened parts.

Functionally I haven't had a problem with MIM or forged parts. Maybe I need to shoot more and report back later.

Emotionally I think its kind of sad to see guns that have been produced for decades or longer in the case of the 1911, with forged and machined parts transition to MIM parts.