Remember, in the Old Days B.M. (Before MIM), many 1911 parts were made from castings.   Some still are, but MIM has replaced many parts that were cast.

Compared to MIM parts, cast parts have lower density and are much more likely to contain air voids.  If it's done correctly, MIM produces a much better part than casting, and rivals the strength of barstock (billet) steel parts.

Where MIM doesn't work well is in things like extractors and parts which are expected to act as springs.  For this, barstock still seems to work better.  

Regarding the observed broken MIM parts here and there, I have a feeling that there is a parts supplier out there somewhere that made a bad run or five of parts, and subsequently sold these parts to several 1911 makers.  I'd bet that if you could trace the origin of every broken part, you would come up with some sort of general pattern that would point back to the guilty party.

I don't think we are going to be able to get away from MIM completely in a 1911, but that's OK with me.  There are certain parts that it just makes sense to produce this way, parts like grip safeties, mainspring housings, etc.  If it comes down to a casting vs. a good MIM part, I'll take my chances with MIM.

Also there is a thread at Pistolsmith.com that covers this subject in depth.

www.pistolsmith.com/viewtopic.php?t=18437

Thanks, good link, intel is good...

Is there a time frame for when MIM started being used wide spread in the 1911 industry?

Who was the first?

Are there any companys that make 1911s that do not use any MIM or CAST parts at all?

If there is I would like to know who they are so I can buy from them.

Quoted: I just recieved ( two days ago) a Wilson Combat tactical mag release, appears to be MIM. So now I'm wondering, just where is a guy gonna have to look to find non-MIM parts? I see a lot of Ed Brown parts are apparantly barstock-derived, some from Wilson are listed as such, and others of course, but does any body know of a supplier that offers a complete line of internals for 1911 that are not MIM? I love my old 1911, and the only MIM part in it currently is that aforementioned Tac release, and I'll run it for awhile and see what happens. But I've got plans to build some new pieces for myself in the near future, just because I seldom get the chance to build stuff for myself, I wanted to go from bare frame and slide, mostly just for the satisfaction of it. But where or where do ya gotta go to get some straight-steel parts? Any ideas?

get a Caspian catolouge, they tell you if it's barstock or not.

tag.

I'm not sure, but would assume a CM ambi safety is MIM.  

I was working with one the other day and put it in and the grip safety was binding and ambi safety operating very slugishly, and I kept dissassembling and re-assembling it to finally find that the problem was that the center of the pin was like 4 thousandths out of round and causing the binding.  

That really was needless grief.  I also began to see the beauty in the style that doesn't have the pin connect within the grip safety- that's just stupid.  

Anyone know the MIM content in:

STI Trojan

Smith & Wesson 1911PD (Scandium Frame)

?

Quoted: Quoted: Of the other numerous MIM parts, like grips safeties, exctractors, sears, disconnectors, mag releases, mainspring housings etc., I have seen no premature parts breakages.   Broken MIM mag catch from my Kimber, which rendered the gun inoperable. Luckily it happened at the range... www.hunt101.com/img/334649.jpg Quoted: Perhaps you can enlighten us as to what "metal cutting business" means. FWIW, there are alot of campanies out there that do nothing but cut metal for other companies. I worked at one for awhile as a plate saw operator. Boring, boring, boring job.

my ULTRA CARRY did the nsame thing.i have a new one.i hope its not mim but im sure it is sine i didnt specifie.

Love mimbers,,,,,,,,,,,,,,,,,,,,, but hate MIM

Kimbers originally did not use MIM parts, the parts weren't around yet.  I bought a Custom six months after it came out.  It wasn't MIM.
The MIM parts came about a year or two later.  You can see it, look for seams.  They try to place them carefully so the lines don't show, but when you look at a part and see a line in the steel where there shouldn't be a line, it's a MIM part.
The Kimbers use Chip McCormick parts.  Looking at the McCormick safety on my Springfield, it is a MIM part.  It is also the only part I could find that fit my needs - stainless, extended, single.  The metal was softer than I expected, it was noticeable when I fit it.  It seems okay.  The geometry of the safety shouldn't stress the part in a way to make it wear.
The McCormick slide stop is also MIM.  I just field stripped the gun and the slide stop is wearing.  It will be replaced, there are only a few hundred rounds on it.
The Ed Browd guide rod and guide look like bar stock.  So does the Ed Brown ejector.  I can't tell what the Springfield bushing is, I think it's a casting.  It's departing anyway.
The Brownells disconnector didn't appear to be MIM.  If it is, they hid it well.  The Wilson hammer is not MIM, neither was the STI sear.  The Brownell's / JTM mainspring housing seems to be a casting, but its an old part, so they may have changed their methods.

If you want a good look at MIM parts, go play with a NEW Smith and Wesson revolver.  They don't even try to hide the molding lines.  You can get a good idea of how steel looks when it is MIM.  You don't see tool marks and the metal has no striations on it.  The Smith hammers and triggers are large MIM parts, so you'll get a good look.  Interestingly, they still case hardedn the parts even though they are MIM.

Quoted: Kimbers originally did not use MIM parts, the parts weren't around yet.  I bought a Custom six months after it came out.  It wasn't MIM.

Then you have the only Kimber I've ever heard of that wasn't chock full-o-MIM. I also had a VERY early Pro CDP and it was full of MIM parts.

They've always used MIM parts in their 1911's and even brag about  it in their catalogs:

"Manufacturing innovation played a huge part in Kimber's success. Metal Injection Molding (MIM) is a process Kimber pioneered in the gunmaking world. Small parts like the slide release, thumb safety, and sights are made by this method. MIM parts are far superior to castings used by other manufacturers, and essentially have the strength of those machined from steel."

Quoted: The MIM parts came about a year or two later.  You can see it, look for seams.  They try to place them carefully so the lines don't show, but when you look at a part and see a line in the steel where there shouldn't be a line, it's a MIM part.

The biggest tell-tale sign of MIM is not a visible seam, but the circular markes where the material was injected into the mold. Even quality forged parts can have obvious seams.

My Colt 1991 slide stop failed about 10 years ago.  I presume this part was not MIM, unless someone knows different.  Stuff breaks.  Unfortunately.  I don't know you can blame MIM for everything.

Well about 40 years ago, our 1911's were breaking all the time.  And they didn't have a single MIM part in them.

What changed?

It's much ado about nothing.

MIM done well will work well, Bar stock done well will work well.

MIM done poorly will not work well, Bar stock done poorly will not work well.

If Baer/Nighthawk etal. are so reliable, why do they have to make any other parts than the ones in the originally sold pistol?  NewsFlash they break too.  Now take 50,000 BAER pistols (that would take them 5 to 10 years to manufacturer) and 50,000 Kimbers or Springfield's.  Maybe, just Maybe the BAER's may be more reliable.

But is that because of parts, or care of assembly?  We will never know.

Actual failure rates interest me more than anecdotal evidence.  Personally I have seen more bar stock stuff break in weapons than MIM.  I have a year or two on my chassis, and most of the older weapons I have used seen were frankly bar stock because they were from an era when most weapons were made from bar stock parts.

I don't see the newer weapons breaking anymore frequently than the old ones.

Hell, Kimber put a lot of gunsmiths out of business.  Why, because unlike the old bar stock Colts, they are/were built better, and a lot more reliable.  (first thing you did with a brand new Colt, was send it to your smith to get a reliability job!)

No, the MIM vs Bar stock pissing contest is a rationalization for elitists and high end manufacturers to justify some of their high cost.  If only bar stock will save your life, May I suggest a cast Iron umbrella to avoid meteorites too.  Quality custom pistols are what they are because of the care and time assembling them.  A custom pistol with MIM quality parts will be just as reliable as a Custom pistol with Bar Stock quality parts.

Anything wrong with it no, except for the constant drum beat to tell folks with weapons that are stone reliable that those same weapons are not reliable.

But, then that's why they invented many things.  As ole PT Barnum once said, there's one born every minute.

Go figure.

Fred

Semper Fi

height=8

Quoted: Are there any companys that make 1911s that do not use any MIM or CAST parts at all? If there is I would like to know who they are so I can buy from them.

No MIM at Nighthawk custom. I think Wilson also abandoned MIM after some problems

Quoted: Quoted: Are there any companys that make 1911s that do not use any MIM or CAST parts at all? If there is I would like to know who they are so I can buy from them. No MIM at Nighthawk custom. I think Wilson also abandoned MIM after some problems

Thanks for the info!

Do the anti-MIM folks really believe that, in this day of suit-happy consumers and nastier lawyers, gun makers (who also have lots of lawyers and the potential for suits) would use cheaper and "inferior" parts when faced with such loss potential just to save a few dimes? Did their own testing not play a key role in going the MIM route?

I'm not saying MIM is the equal to forged steel, I'm just saying we are NOT the first ones to consider the issue...gun maker top brass & legal departments most assuredly did.

a coupel of questions-

Colt firing pin stop and slide stop from Brownells - cast, MIM, or barstock?
Kimber extractor - MIM?
regular Wilson FP stop - Barstock, machined, or what? (not the Bullet Proof part)

Rock River ads claim no MIM in their 1911.

Quoted: Rock River ads claim no MIM in their 1911.

SWEET! I have a RR catalog and it doesn't say anything about if their 1911s have MIM in them or not.

MY KIMBER UC HAS HAD ONLY ONE FAILURE IN THE PAST 5 YEARS OF LIGHT USE.Yes the failure was due to a part breakage.A  MIM part to be precise.The magazine release thingie broke .the lead to the mag falling out .without the mag firmly in place your out of luck.You cant hold the mag up in there firmly enough to cycle the pistol.Iv'e never had that kind of a failure before.I replaced the mag release with a forged unit.

Quoted:  With respect to many of the above comments on MIM, here is my take: MIM is a cheap way of making a part that looks right and is actually about halfway right.  Okay....maybe three quarters. Essentially powdered metal with a flow agent and binder mix is injected into a net or near net shape mold. The lack of subsequent post processing is what makes this a very economical process. The amount of time saved in manufacturing by using the MIM process is immense.  Anyhow the metal/binder matrix is compressed under VERY heavy pressure so that the binders hold the part in shape. The part is then ejected from the mold and then transferred to a series of heat treat processes. The first of which removes ( melts out ) the binder and other agents from the matrix. The second sinters the metal so that cohesive molecular bonds are formed between the compressed molecules of steel. Between the compaction and the sintering processes the parts are very brittle and any flaws inherant in the original forming process or the transfer process are passed along to the part. The molecular density of a MIM'd part is about 80 to 90 percent of a conventional barstock part. HOWEVER the molecular STRUCTURE is, in no WAY, SHAPE OR FORM even close to that of a forging or barstock. Thanks...I'll stick with barstock or a forging.....the only part left on my Colt that is MIM'd is the plunger tube. Friends don't let friends use MIM!!!!

++++1