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View Full Version : Swap out MIM CM9 parts for PM9 equivalent?



70CM9
09-11-2013, 05:56 PM
I've wondered about this for a bit but haven't seen any info.

From my understanding of the situation, in addition to the less-machined and laser-engraved slide, staked front sight, and traditionally rifled barrel, the CM9 uses some MIM parts - specifically the slide stop lever and, I believe, the guide rod - that are NOT used in the PM9.

If this is indeed true, can the MIM parts be swapped out for the PM9 equivalents, or is there some dimensional difference between these parts to keep that from happening?

jocko
09-11-2013, 06:07 PM
u can swap them out buyt your sure wasting money doin so. those parts will give yuu no moreissues than a forged part. IMO a waste of good money. If it ain't broke don't fix it. becuasse it might be a lower cost way to produce it does not mean it is of lesserquality. Kahr woul dnot go that route either. LEAVE THE FOKKERS ALONE..

CJB
09-11-2013, 07:43 PM
There are no forged parts in a Kahr, except for either type of barrels.

The P/PM/TP slide stop is a cast lever with a ground pin attached.

All 1911 slide stops have been cast/MIM for decades, zero issues that you hear of.

Jocko... just a minor correction for claritiy. Lots of folks confuse "forged" (ie, metal beat into shape with a hammer) and machined. In Kahr's case, its really a bit of machining (grinding) along with a cast lever section.

b4uqzme
09-11-2013, 09:52 PM
There are no forged parts in a Kahr, except for either type of barrels.

The P/PM/TP slide stop is a cast lever with a ground pin attached.

All 1911 slide stops have been cast/MIM for decades, zero issues that you hear of.

Jocko... just a minor correction for claritiy. Lots of folks confuse "forged" (ie, metal beat into shape with a hammer) and machined. In Kahr's case, its really a bit of machining (grinding) along with a cast lever section.

Regardless, Jocko's right. I wouldn't expect any less service out of the CM's MIM parts. If you break one, you can change it out then. But don't hold your breath. :)

Popeye
09-13-2013, 12:17 PM
IMO the fact that there some MIM parts on a SD pistol like the CM9 means absolutely nothing. If I was to change anything on the CM 9, I would change the sights to night sights. That's where I'd spend my money. On something useful and that will make your CM9 a better pistol all the way around.
As far as MIM parts go, I'd be willing to bet Abrams Tanks have a few MIM parts in them. So I sure wouldn't give much thought to the MIM parts in your 9mm pistol. :D

skiflydive
09-13-2013, 12:28 PM
Jet engine turbine blades are MIM

muggsy
09-13-2013, 12:32 PM
MIM is metal injection molding. It's a manufacturing process that eliminates the need for a lot of machining. It doesn't make a gun less reliable. It only makes them less expensive. I would prefer to have a metal front sight on a CM or CW Kahr, but not necessarily a night sight. You are not very likely to use the sights in a gunfight. You are far more likely to point and shoot.

Popeye
09-13-2013, 12:42 PM
MIM is metal injection molding. It's a manufacturing process that eliminates the need for a lot of machining. It doesn't make a gun less reliable. It only makes them less expensive. I would prefer to have a metal front sight on a CM or CW Kahr, but not necessarily a night sight. You are not very likely to use the sights in a gunfight. You are far more likely to point and shoot.

Agree Muggsy but I guess that would depend on what the pistol is being used for. In My case the PM9 was also used as a HD pistol at night when I didn't feel like opening the safe to grab the PO-1 or the 1911 to put on the Night stand, and was a back up to the SG. Those NS on the PM9 I thought were great as you could see them with tired eyes, but yet they were not to bright as to flood each other out.

kerby9mm
09-13-2013, 04:32 PM
So the slide is mim. I don't think so. I would think it is forged. I was disappointed to find out that tge frames on my mk's are cast but I got over it.

Ultona
09-16-2013, 11:44 PM
MIM explanation from a manufacturer who knows:

"The piece starts out larger than it will end up because it's a mix of plastic and metal. The plastic is melted out leaving a metal part that looks terrific but is lacking in some important material properties. (It's akin to sintered metal.).........It has been suggested to us by folks selling the process that we could make some of our small parts like catches and triggers that way, but we refuse to do it."

MIM parts are not junk, but they are certainly not as good as a forged part, Hot Isostatic Pressing casting or even a quality produced traditional casting that uses pure metal to begin with. MIM parts tend to fracture or crumble when they fail instead of bending or giving some warning of failure like traditional parts often do.

That being said, for a large part like the slide stop on a CW9 ect. I think you can "get away with" an MIM part. However, I would not be happy with Kahr making smaller critical internal moving parts like the cocking cam that way. I can assure you MOST companies would have made ALL the parts in a K9, P9, ect using MIM LONG ago, and I'm proud of Kahr that they have not gone that way, it is part of the reason I love Kahrs so much, as I can buy a new K9 and it will be built the same way as one from the 1990's, not horribly cheapened and bristling with key locks like some gun companies have done to their guns.

One really bad side effect of MIM has nothing to do with the parts per se. That is that parts require little to no fitting, so you end up with workers who can't.......you guessed it.....fit anything. So when something does need attention they are stumped. I sent in a new S&W 438 that had a very creepy trigger due to a flaw in the MIM hammer which should have been an easy fix and it ended up being ruined by the employee trying to fix it. They were nice enough to give me a new gun, which I still have, but it points out the obvious.

Popeye
09-17-2013, 04:40 AM
So the slide is mim. I don't think so. I would think it is forged. I was disappointed to find out that tge frames on my mk's are cast but I got over it.
Who said the slides were MIM?

kerby9mm
09-17-2013, 05:30 AM
There are no forged parts in a Kahr, except for either type of barrels.

The P/PM/TP slide stop is a cast lever with a ground pin attached.

All 1911 slide stops have been cast/MIM for decades, zero issues that you hear of.

Jocko... just a minor correction for claritiy. Lots of folks confuse "forged" (ie, metal beat into shape with a hammer) and machined. In Kahr's case, its really a bit of machining (grinding) along with a cast lever section.

I was referring to this post when I commented on the slides

Ultona
09-17-2013, 09:19 AM
This brings up a good point. Why don't companies MIM slides and frames? I believe the characteristics of MIM I brought up in my last post are probably the reason, combined with the fact that the plastic/metal mix material used for MIM costs about 10 times more than "normal" steel, so maybe on larger size items it doesn't make as much financial sense.

jocko
09-17-2013, 09:54 AM
no doubt in my mindis is allabout the cost factor.Just because it is machined does not not make it bettereither. alot of variable to consider..

skiflydive
09-17-2013, 12:26 PM
I agree with Jocko.

As a manufacturer I deal with process cost vs build quality every day.

Let's look for a moment at the PM9 slide stop, which some consider superior to the CM9 slide stop because it isn't MIM.

Some have said the PM9 piece is forged. The lever portion of it may be but the whole thing isn't. It's a 2 piece part because forging a piece that shape and then machining it would be a nightmare. The round part is inserted into the lever part. Forge dies (and forging) are effin' expensive and if it is in fact a forging, there's a TON of machining operations and finishing operations to do after the forge to come up to the finished state and then the pin, which wouldn't be forged, has to be assembled to the lever part and done reliably enough to stay there without coming apart.

MIM parts are molded in the same kind of molds and machines as plastic injection molding. LOTs cheaper than forging. The part can be molded as one piece and after the final heat it ends up being "Near net shape" which means no, or very little, machining. Throw a few hundred in an abrasive tumbler for several minutes to give a nice finish and you're done. No assembly, no muss, no fuss, no bother. Because the pin isn't pressed/assembled to the lever there's not much chance it'll come apart at that joint hence, the part is probably stronger in the long run than the assembled one.

Do they use MIM because it's cheaper? Of course they do...the same as we go to Wally World for ammo. Is the Wally World ammo somehow worse than the higher priced stuff down the street? Probably not. Is the CM9 slide stop worse than the PM9 one? Probably not. It might even be better because it's a one piece part.

For more layman's info on the MIM process see here (http://en.wikipedia.org/wiki/Metal_injection_molding)

jocko
09-17-2013, 01:06 PM
I think the PM9 lever itself is a MIM part. the pin is of high priprotory steel,what ever in the fokk that means. I sure wouldnot spend the bucks for the PM side stop lever.IMO a sales selling point .

O'Dell
09-17-2013, 02:34 PM
I think the critical question here is: Have any of the MIM slide stops ever failed? Someone else may know better than I, but I've never heard of it happening.

jocko
09-17-2013, 02:37 PM
I have seen one of the MIM pins broken on this forum but it has been a few years ago..I do trhink though we have seen more "out of spec" machined slide stops being replaced..... Just sayin

muggsy
09-17-2013, 04:22 PM
I think the PM9 lever itself is a MIM part. the pin is of high priprotory steel,what ever in the fokk that means. I sure wouldnot spend the bucks for the PM side stop lever.IMO a sales selling point .

Jocko, the word is proprietary. For your edification, click on the link for a definition. Ya larn sumpin new ever day. Just sayin.

http://whatis.techtarget.com/definition/proprietary