MIM

16-Dec-13 – 10:46 by ToddG

In response to the report of the broken SIG extractor from a few days ago, quite a few folks both here and on various forums have resorted to blaming the fact that the part was made using a process called MIM, metal injection molding. The shooting community as a whole has a very negative — and very ignorant — attitude toward MIM.

There’s good MIM and bad MIM. Some parts are more suitable for MIM’ing than others. In fact, part of the reason SIG changed its extractor design was so that it would be more appropriate to MIM limitations. SIG has been using MIM’d parts for close to two decades. The hammer, for example, was being MIM’d long before I started working there in 2002. How many SIG hammers have you heard of that broke?

It’s no secret that I consider the HK P30 the best handgun on the market. It has MIM parts. I shot a few rounds through one and didn’t have any of those parts break.

The incredibly critical sear on my current Springfield 1911, which is kept cocked & locked twenty-four hours per day, is a MIM part. That gun has over 62,000 rounds through it so far and the sear is good as new.

MIM itself isn’t bad. MIM just got a bad rap because one of the first companies to use MIM parts en masse, Kimber, did so in a spectacularly bad way. Bad MIM, like bad casting or bad forging, is still bad. But that doesn’t mean all MIM is bad, and in fact the majority of us are carrying guns with plenty of perfectly good MIM parts.

We’re also driving cars with hundreds of perfectly good MIM parts, fly in airplanes with plenty of perfectly good MIM parts, etc.

MIM isn’t bad. Bad MIM is bad. There’s a difference. Don’t be afraid of MIM.

Train hard & stay safe! ToddG

  1. 10 Responses to “MIM”

  2. Any other company using the MIM process to make extractors?

    By Frank on Dec 16, 2013

  3. Todd, I think this is all the more reason for you to ring out one of the new production Sig Sauer P226s! What a great time to test those MIM parts!

    By jbourneidentity on Dec 16, 2013

  4. Will the gadget be MIM?

    By Tyler on Dec 16, 2013

  5. In answer to Frank, I bought an Argentine Sistema Colt 1911, whose extractor proved to be MIM. I’m not sure who made it (the Argentine originals were not MIM), but it broke before I put 500 rounds through the pistol.

    I think you can make a good extractor through MIM, and SIG’s record to date suggests that is correct. Still, extractors are subject to lot of stress and heat so if it isn’t done right they are going to be more likely to break.

    By SteveJ on Dec 16, 2013

  6. Frank: Yes, Glock.

    By JV on Dec 16, 2013

  7. MIM as a process is also perfectly suited to making high strength small parts for firearms.

    Not to be an unnecessary echo, but many connecting rods in modern automobile engines are also a powdered metal.

    Thanks for writing this post Todd.

    We are long overdue for MIM myth busting.

    By fixer on Dec 16, 2013

  8. I would love to see a SIG get put through the paces. Personally, I think one of the Sig Pro pistols would be interesting…

    By John on Dec 17, 2013

  9. Totally agree…the HK P30 is the best handgun on the market.

    By Matt on Dec 17, 2013

  10. More on good MIM:

    http://www.mpif.org/designcenter/mima_searchresults.asp

    http://www.remingtonpmpd.com/design/principles.asp

    By lyford on Dec 17, 2013

  11. Agree 100% with your opinion on MIM. The P30’s, and their terrible triggers no matter which variant, not so much…

    By CK1 on Dec 17, 2013

Sorry, comments for this entry are closed at this time.