Darkside852003
Member
What parts on my Kimber Custom II are MIM?
Thanks,
Jeff
Thanks,
Jeff
Kimber MIM
- Thread starter Darkside852003
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stans
Member
If I remember correctly, barrel bushing, hammer, sear, disconnector, grip safety, thumb safety, slide stop, extractor, ejector, plunger tube, mainspring housing, all of the parts in the Swartz firing pin safety system and maybe the firing pin stop. Pretty much all of the small parts are MIM in the current productin Kimbers. I am sure someone with more knowledge will come along and correct any errors in this list.
1911Tuner
Moderator Emeritus
MIM?
stans pretty well nailed it. If I'm not mistaken, the strut is also MIM...
or cast...? I think Kimber abandoned the MIM barrel bushing a while back, though. Kruzr will soon see this and give us the real skinny.
stans pretty well nailed it. If I'm not mistaken, the strut is also MIM...
or cast...? I think Kimber abandoned the MIM barrel bushing a while back, though. Kruzr will soon see this and give us the real skinny.
JohnBT
Member
Well, some years ago I had a well respected gunsmith post that it just wasn't so when I posted the following quote from the '99 Kimber catalog, but here it is again from page 5 (Custom & Custom Target guns) FWIW:
"Barrel bushings, which lock the barrel in position, are machined from stainless steel blanks."
Maybe they're stainless MIM steel blanks?
John
"Barrel bushings, which lock the barrel in position, are machined from stainless steel blanks."
Maybe they're stainless MIM steel blanks?
John
1911Tuner
Moderator Emeritus
MIM Bushings?
One way to know for sure...if ya can't find the sprue mark on it.
Lay it flat on an anvil...put the ball end of a small ball-peen hammer in the skirt, and whack the flat end of the hammer like you were gonna expand the skirt a little. If it splits, it's MIM. It won't take much force to bust it.
Ask me how I know...
One way to know for sure...if ya can't find the sprue mark on it.
Lay it flat on an anvil...put the ball end of a small ball-peen hammer in the skirt, and whack the flat end of the hammer like you were gonna expand the skirt a little. If it splits, it's MIM. It won't take much force to bust it.
Ask me how I know...
45R
Member
Kimber produces so many 1911s each year. Are MIM parts that much of an issue?
1911Tuner
Moderator Emeritus
So Many
45R asked:
Kimber produces so many 1911s each year. Are MIM parts that much of an issue?
_________________________
For range queens, heirlooms, conversation pieces, status symbols and toys...it's not.
When it can make the difference between walkin' away and squirmin' around on the ground tryin' to stuff my thumb in a sucking chest wound 'til the paramedics get there...You betcha it's an issue. It is for me, anyway.
Of course...my opinion is just that.
Luck!
Tuner
45R asked:
Kimber produces so many 1911s each year. Are MIM parts that much of an issue?
_________________________
For range queens, heirlooms, conversation pieces, status symbols and toys...it's not.
When it can make the difference between walkin' away and squirmin' around on the ground tryin' to stuff my thumb in a sucking chest wound 'til the paramedics get there...You betcha it's an issue. It is for me, anyway.
Of course...my opinion is just that.
Luck!
Tuner
Kruzr
Member
Here I is.
......pretty close.
The following parts have circles that resemble MIM mold popper marks. (What's the saying........if it looks like MIM and quacks..........oh wait, that's ducks.
) Locations of the mold marks are noted.1. Slide stop (inside surface near front)
2. Thumb safety (inside surface near front)
3. Sear (outside surface on "feet")
4. Disconnector (on starboard side)
5. Swartz push rod (starboard side above and below slot)
6. Swartz FP block (top)
7. Grip Safety (in hammer notch and in front of notch)
8. Hammer (body, both sides)
9. Mag Catch (not the turning locking pin) (marks on top)
10. Firing Pin Stop Plate (inside surface)
11. Ejector (inside)
12. Plunger tube (somewhere ?)
Kimber invested big bucks in 2 machines that spit out bushings from billets very quickly a few years ago. Extractors are machined from some kind of non springy steel but not MIM. Kimber MSH's are polymer unless you get one with the funnel magwell.....those are cast.
JohnBT
Member
Whacking a Kimber bushing sounds like fun. I saved the one I took out of my Stainless Gold Match, but I don't know how quickly I can find it. Oh well, maybe another day.
JT
JT
45R
Member
Tuner,
I left my PC after posting that Q and thought....damn I am in CA. People in other states actually carry.....and rely on the guns for SD purposes. I come back and Wham your response
Anyways thanks for keeping a brother honest
Best
45R
I left my PC after posting that Q and thought....damn I am in CA. People in other states actually carry.....and rely on the guns for SD purposes. I come back and Wham your response
Anyways thanks for keeping a brother honest
Best
45R
Darkside852003
Member
Thanks everyone for helping out. I am in need of a new project, so after I swap all these MIM parts its getting sent to magna port. Then off to refinishing........oh the wallet is in pain.
Thanks,
Jeff
Thanks,
Jeff
bountyhunter
member
Wouldn't it be easier and cheaper to just buy a better gun that doesn't need it's internals swapped out? Street price on STI Trojan right now is about $900. I'm not sure if STI is still 100% MIM free, but their hammer and sears are first rate. You get the bonus of having a hand fitted slide/frame/barrel as well.
Kruzr
Member
It's even easier just to shoot it as it is......like LAPD Swat does.
bountyhunter
member
Maybe, but I am never going to bet my butt on a gun with any long thin parts made from MIM because the process is not well suited for that. A grain defect and it's a catastrophic failure. No slide stops, extractors, hammer struts or disconnects.
Bountyhunter has a good point ..
But more important, I believe those big-buck SWAT guns had the cheaper lockwork swapped out. It isn't that Kimber can't build a decent gun when they want too - but that only the rich and the government can afford it when they do.
But more important, I believe those big-buck SWAT guns had the cheaper lockwork swapped out. It isn't that Kimber can't build a decent gun when they want too - but that only the rich and the government can afford it when they do.
Kruzr
Member
The LAPD and the Tacoma PD guns are stock Kimber.......all the MIM intact.
The Marine DET 1 pistol had some parts changeout.
Kruzr
Member
I've heard that LAPD paid somewhere around $600 apiece. And........they are stock.
I'll take your word for it ...
Not the question is, how well will they hold up?
Past threads on this forum have detailed thay have problems, especially with broken slide stops. I don't wish any troubles on anyone, but I think they made a poor choice. MIM parts do not have a good reputation so far as 1911 pistols are concerned, while in other makes and models they seem to work fine.
I wonder if the respective police departments you mentioned know what their guns have in the way of internal parts. Obviously the USMC does.
Not the question is, how well will they hold up?
Past threads on this forum have detailed thay have problems, especially with broken slide stops. I don't wish any troubles on anyone, but I think they made a poor choice. MIM parts do not have a good reputation so far as 1911 pistols are concerned, while in other makes and models they seem to work fine.
I wonder if the respective police departments you mentioned know what their guns have in the way of internal parts. Obviously the USMC does.
Master Blaster
Member
My E-mail to Kimber and their reply Regarding the MIM parts in my TLE II
Greetings,
Three months ago I bought a new TLE II.
I am considering carrying it on a daily basis as my CCW defense gun.
There is one problem though. I have read about and seen pictures of two of the mim parts in my Kimber that have broken unexpectedly on other people.
Those parts are the firing pin safety, and the slide stop.
I find it hard to trust an MIM part in a high stress application such as this especially when it could cost me my life should the gun refuse to function when I need it most.
How frequently do these parts break, is there some defect in them that causes this to happen? Are there any non mim parts that I can use to replace these parts???
I am really disappointed that after I spend $800 on a handgun that I may not be able to rely on it due to cost cutting measures such as using cheap mim parts where machine barstock would be a more reliable solution.
I look forward to a prompt response.
Sincerely,
Andrew R. Cohen M.B.A.
Their Reply to Me:
From: Devin Antonovich [[email protected]]
METAL INJECTION MOLDING : MIM
MIM: A process in which powdered chrome moly steel is mixed with a polymer carrier, placed into an oversized mold, and sintered. The part shrinks to size in the process, then heat-treated.
The result is intricate parts which are:
- extremely accurate
- more dense than investment cast parts
- 98% of the strength of a forged part
Many of the important internal parts on a Kimber are MIM parts:
Slide Stop
Thumb safety
Grip safety
Disconnector
Sear
Hammer
Strut
Magazine catch
Note: The ONLY Polymer part on the Kimber is the mainspring housing.
Greetings,
Three months ago I bought a new TLE II.
I am considering carrying it on a daily basis as my CCW defense gun.
There is one problem though. I have read about and seen pictures of two of the mim parts in my Kimber that have broken unexpectedly on other people.
Those parts are the firing pin safety, and the slide stop.
I find it hard to trust an MIM part in a high stress application such as this especially when it could cost me my life should the gun refuse to function when I need it most.
How frequently do these parts break, is there some defect in them that causes this to happen? Are there any non mim parts that I can use to replace these parts???
I am really disappointed that after I spend $800 on a handgun that I may not be able to rely on it due to cost cutting measures such as using cheap mim parts where machine barstock would be a more reliable solution.
I look forward to a prompt response.
Sincerely,
Andrew R. Cohen M.B.A.
Their Reply to Me:
From: Devin Antonovich [[email protected]]
METAL INJECTION MOLDING : MIM
MIM: A process in which powdered chrome moly steel is mixed with a polymer carrier, placed into an oversized mold, and sintered. The part shrinks to size in the process, then heat-treated.
The result is intricate parts which are:
- extremely accurate
- more dense than investment cast parts
- 98% of the strength of a forged part
Many of the important internal parts on a Kimber are MIM parts:
Slide Stop
Thumb safety
Grip safety
Disconnector
Sear
Hammer
Strut
Magazine catch
Note: The ONLY Polymer part on the Kimber is the mainspring housing.
bountyhunter
member
The Kimber reply is true as far as it goes, but it doesn't really answer the question at all. I don't think MIM is a plague upon the land, but I think gun makers did not use common sense in deciding what pieces to apply it to. He is correct in his description of the MIM process and that MIM are typically 95% to 97% as dense as forged parts. This compares to about 70% as dense for most cast parts. But density is not the only consideration: some of the best 1911 frames on earth are made via casting, so that process can produce an excellent result if done properly.
The "if done properly" caveat is the key here: in a casting process, a molten liquid is poured into a mold and it hardens. The primary concern would be an air void (buble) somewhere inside. This is easily avoided if the metal is properly heated and the mold is designed right.
In MIM, the metal particles are mixed with a polymer (glue) and then forced into the mold under pressure. I see three possible sources of a defect:
1) The "slurry" (glue and particle mix) is not thoroughly blended and there are clumps of metal particles or clumps of glue, either will cause a defect.
2) Air void in the piece because the air in the mold is not completely displaced when the mix is forced in. More likely in MIM because the mixture is thicker and not a molten liquid.
3) Metal particles not all the same size. Any large "flyers" mean that there may be an unseen weak spot.
It certainly is possible to make perfect MIM parts.... if the process is perfect. But given that MIM was introduced to save money, and the quality of guns in general has declined over the last five years, that does not warm my heart.
IMHO, MIM is not a logical choice for long thin pieces subject to high stress because of the fact a defect will cause a catastrophic failure. Hammers and trigger maybe..... sears makes me cringe because the long thin nose is likely to snap.... slide stops, extractors and struts? Fugedddaboudittt....
The "if done properly" caveat is the key here: in a casting process, a molten liquid is poured into a mold and it hardens. The primary concern would be an air void (buble) somewhere inside. This is easily avoided if the metal is properly heated and the mold is designed right.
In MIM, the metal particles are mixed with a polymer (glue) and then forced into the mold under pressure. I see three possible sources of a defect:
1) The "slurry" (glue and particle mix) is not thoroughly blended and there are clumps of metal particles or clumps of glue, either will cause a defect.
2) Air void in the piece because the air in the mold is not completely displaced when the mix is forced in. More likely in MIM because the mixture is thicker and not a molten liquid.
3) Metal particles not all the same size. Any large "flyers" mean that there may be an unseen weak spot.
It certainly is possible to make perfect MIM parts.... if the process is perfect. But given that MIM was introduced to save money, and the quality of guns in general has declined over the last five years, that does not warm my heart.
IMHO, MIM is not a logical choice for long thin pieces subject to high stress because of the fact a defect will cause a catastrophic failure. Hammers and trigger maybe..... sears makes me cringe because the long thin nose is likely to snap.... slide stops, extractors and struts? Fugedddaboudittt....
Kruzr
Member
bountyhunter, if you ever get a chance to see the MIM process, don't miss it, you'll see how your concerns aren't applicable. They aren't metal particles, it's more "like" powdered metal. The slurry is homogeneous when injected under pressure into the molds. Air voids aren't a problem at this stage. When voids appear in MIM, its a result of the wash process. Most MIM failures are a result of improper sintering, just like many steel failures are a result of improper heat treating.
As far as holding up, the range rental Kimber Custom that we have now has over 120K rounds through it. Only the Glocks have held up better. We have broken 2 Kimber thumb safeties on the paddle, one Colt thumb safety on the post and an Ed Brown safety on the post.......so it isn't just MIM. The sear and hammer were replaced at about 100K when the gun went full auto on a shooter. The Colt NRM rental we had was retired at 40K rounds when the slide developed an axial crack. (Colt replaced it and we sold it).
LAPD has had theirs for about 2 years now and they seem to be very happy. If anyone knows an LEO, the LAPD Swat armorer is happy to talk about their experiences with their pistols.
As far as holding up, the range rental Kimber Custom that we have now has over 120K rounds through it. Only the Glocks have held up better. We have broken 2 Kimber thumb safeties on the paddle, one Colt thumb safety on the post and an Ed Brown safety on the post.......so it isn't just MIM. The sear and hammer were replaced at about 100K when the gun went full auto on a shooter. The Colt NRM rental we had was retired at 40K rounds when the slide developed an axial crack. (Colt replaced it and we sold it).
LAPD has had theirs for about 2 years now and they seem to be very happy. If anyone knows an LEO, the LAPD Swat armorer is happy to talk about their experiences with their pistols.
What's with all these thumb safeties breaking...not an "impact" part so to speak.
Glock 9's or 45's holding up better?
I have 10's of thousands on a MIM sear, disconnector, cast hammer and no breakages. It appears when MIM is done properly, there should be no problems for certain parts on production guns.
Of course, when I have the trigger redone, I'll go barstock. Not enough difference in price at retail to save money using MIM parts.
Glock 9's or 45's holding up better?
I have 10's of thousands on a MIM sear, disconnector, cast hammer and no breakages. It appears when MIM is done properly, there should be no problems for certain parts on production guns.
Of course, when I have the trigger redone, I'll go barstock.
Not enough difference in price at retail to save money using MIM parts.bountyhunter
member
I don't smith enough guns to have a large sample, but based on posts from those who do: MIM slide stops are not holding up well, and I would not want an MIM extractor.
As for the "fine powder" and "well mixed slurry" claims, my problem with that is what I see: I do trigger jobs on new SW revolvers and the surfaces of the triggers and hammers are very bumpy which does not indicate a good mix. I have not worked on Kimbers, so it's possible there process is better: but my comment still stands. Any manufacturing process has pros and cons, and I think gun makers when too hog wild with MIM just because it's cheap. You would not use MIM for a recoil spring.... but an extractor is also a spring. It deflects every time a round feeds and must retain it's "springiness" to maintain peoper tension.
The point is: if a thin piece is machined from bar stock, that stock may have a defect in it... but in the maching process it will likely break and get thrown away. Both MIM and cast processes have no such "backstop" to quality, so it is fair to say that specific parts machined from stock do give a higher level of confidence in durability than MIM or cast parts.
As for the "fine powder" and "well mixed slurry" claims, my problem with that is what I see: I do trigger jobs on new SW revolvers and the surfaces of the triggers and hammers are very bumpy which does not indicate a good mix. I have not worked on Kimbers, so it's possible there process is better: but my comment still stands. Any manufacturing process has pros and cons, and I think gun makers when too hog wild with MIM just because it's cheap. You would not use MIM for a recoil spring.... but an extractor is also a spring. It deflects every time a round feeds and must retain it's "springiness" to maintain peoper tension.
I don't know that to be true. Most forged gun parts are not heat treated at all, just machined from bar stock which itself was made to a specific hardness or cold rolled to increase it. Some parts are herat treated (annealed) to soften them and increase toughness and some are case hardened for a hard surface layer.
The point is: if a thin piece is machined from bar stock, that stock may have a defect in it... but in the maching process it will likely break and get thrown away. Both MIM and cast processes have no such "backstop" to quality, so it is fair to say that specific parts machined from stock do give a higher level of confidence in durability than MIM or cast parts.
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