MIM Innovation Or Cheap Plastic

[gunguy56]

I bought a Taurus PT1911 right after they were introduced. I took it to the range and shot 100 rounds of WWB .45ACP FMJ ammo. After I got back home from the range, I took the slide off to clean the weapon. When I slid the slide off the frame, the ejector fell out on the workbench. The front leg of the ejector had broken off . The broken part was in the hole for it in the left side of the frame and would not come out. My dealer sent it back to Taurus, and about 2 months later Taurus shipped my dealer a new weapon. The ejector was a MIM part. I immediately got rid of the PT1911. I have probably shot 50,000 rounds through 20 or so 1911's in my 64-yr old life, and this is the only ejector to break. No one can ever convince me that the MIM process is better than machined steel for a part of a weapon designed to save your life....

[mo84]

I work in carbide and the process is generally the same. Good QC is the key to keeping the bad parts from getting through. Sometimes when the parts are pressed it will leave a burr which is a chipping point, which if not caught, could lead to big issues. Sometimes the mix of the powder just isnt right and will lead to more isues. Handeling these parts before they are sintered is an art in its self; so a new employee can and will chip/break unsintered parts quite easily. Even with the relitive high cost of carbide we can produce parts that are super cheap to the distributer. My company puts what they are making per part in the blue print packet, so I can see where the gun manufacturers save when it comes to these parts over forged/ machined parts. Just placing the parts wrong on the boards can lead to issues when they get sintered. When all the steps are done in the correct order and everything is right, MIM parts should have no issues but like everything else, there will always be an exception.

[skeeter]

I bought a Gunsite CCO which was a limited run which had forged Chip McCormick internals which replaced the MIM parts. Gunsite pistols are made to be used a lot and Gunsite knew the MIM parts would not stand up to hard use.

The difference between the Police Remington 870 and the non Police model is the police model has no MIM parts. What does that say?

Colt used to issue their 1911 with MIM extractors to save money but they soon found the cost of repairs was not worth the saving in manufacturing the cheaper MIM parts. A very bad application.

Many MIM parts are outsourced to companies in India and China. I would not think of buying a Made in China pacemaker or firearm.

There are great applications for MIM parts like turbine blades but they do not flex like an extractor and do not take any direct wear. It is all about application. Concrete is a great material which is very strong in compression but who wants a concrete diving board?

[Sturmgewehre]

For every detractor of MIM there are equally respected proponents of MIM.

Take STI as an example:

http://www.stiguns.com/resources/faq/faq-mim/

If you're worried about MIM failures, you probably should stay off commercial aircraft as many parts within a modern jet engine are made using MIM. You might also want to avoid buying most new cars as parts like the crankshaft are made using MIM.

I've personally seen forged parts fail in guns. It was due to improper heat treating, not due to the material used.

Kimber gave 1911's and MIM a bad name with their poorly made parts. There were many years of failures reported with their small parts that made people wrongly believe that MIM was the problem. As with any manufacturing, if you don't do something right it will fail. Kimber was outsourcing their MIM parts to small companies that were the lowest bidders. This was done by the former CEO, Cohen (who now works for Sig and is doing the same thing to their reputation by outsourcing small parts to low bidders Israel).

[Fishing_Cabin]

While I know MIM is becoming more and more used with each day, I have only had a problem with one part which I am told is MIM. That is the factory Colt 1911 ejector. I broke 2, and now I just replace them when I get a new Colt to shoot. Its cheap insurance.

[KyJim]

If you're worried about MIM failures, you probably should stay off commercial aircraft as many parts within a modern jet engine are made using MIM. You might also want to avoid buying most new cars as parts like the crankshaft are made using MIM.

But as another poster noted, it's about application. Extractors, ejectors, and slidestops should not be MIM. Just because MIM may have some use in an airplane does not mean they are as good, for all purposes, in a gun. To date, nobody makes a MIM slide or barrel. Wonder why that is?

BTW, I do have an STI. Great range gun.

[moseley123]

To Vermonter. Your question about MIM, I personally have seen lots of MIM problems.
I build custom guns so i know first hand MIM downfalls. For the average gun owner MIM
can be ok, but for someone who shoots alot i have seen too many failures, everything from these parts bending, cracking, breaking, and the list goes on. I personally would not have these parts in any gun i own, but then i build my own. most people do not have that luxury.
but if you want to know more about MIM my email is listed below.

[email protected]

[DaleA]

Welcome to the forum Moseley.

If you're building guns you probably have a lot to contribute.

This thread is over four years old though and MIM parts get discussed a *lot* and when all is said and done a lot more is said than done.

Personally I just listen to the MIM discussion and don't have anything first hand to contribute one way or the other.

Good luck.

[Evan Thomas]

As Dale, pointed out, this thread is over four years old. Vermonter hasn't been here in several months, and before that, not for a couple of years. I think he has moved on, and reopening this thread serves no purpose.