10-8 Performance Lab, Episode 31: MIM In The 1911

Now do I have to go examine my 1911s and scrutinize the parts? lol.
 
No, shoot the daylights out of them.
Good, I will....hate taking those things apart! lol. The RIA must be getting near 10,000 rounds by now, the Springfield, I bought used so I have no clue....but it's been perfect (except in a "speed rock" drill....lol. It hated that, as did the G19.)
 
If the gun is not a defensive weapon, but has MIM, just shoot the snot out of it.
I have bought two slide stops to replace a MIM slide stop in a Springer, just because. Neither fit, and would require chamfering the frame. They went in the parts box and I’ll keep shooting it "as is".
 
Guess I'd better look at the .45, since I'd like to carry that one.....dang, now I have to get it apart....lol.....
what are you carrying.
 
Meaning what? Don't carry it? Don't put a fiber optic front sight on it? Don't get a straighter trigger? What? lol.
Well, the video is about MIM parts in 1911’s. Many other weapons have MIM parts.

The likelihood of you finding machined forged replacement parts for that CZ Rami, assuming its internals are MIM, is probably slim.

I'd probably advise against changing the trigger if it’s for defense. I don’t say this to everyone, but I think this would be best for you.
 
Well, the video is about MIM parts in 1911’s. Many other weapons have MIM parts.

The likelihood of you finding machined forged replacement parts for that CZ Rami, assuming its internals are MIM, is probably slim.

I'd probably advise against changing the trigger if it’s for defense. I don’t say this to everyone, but I think this would be best for you.
I only intended to do the things I mentioned to the RAMI. The trigger is really curved, I need a straighter one.
But in the interests of learning from experienced gun people, how come you would leave it alone for a defense gun for me?

(Probably because you've seen me shoot? lol.)
 
I only intended to do the things I mentioned to the RAMI. The trigger is really curved, I need a straighter one.
But in the interests of learning from experienced gun people, how come you would leave it alone for a defense gun for me?

(Probably because you've seen me shoot? lol.)
One of the fastest shooters I know won’t change out the stock triggers on his defense weapons.
 
Did he say why? Just curious.
Not screwing with a system designed and demonstrated to work. I personally will change a trigger in a Glock for defense, whereas he won’t. That’s just his thing, but knowing his knowledge of firearms and his ability to operate them very effectively it's a position worth considering.
 
I prefer without...… but truthfully it isn't a big deal if the parts are well made and used in the right application.

Tuner had this topic a while back, and if I recall, MIM parts don't hold up well to shear and impact.
 
IMHO MIM in 1911s is solely there to allow a company to met a price point. People want a $60o 1911 with all the bells and whistles right out of the box. The only way to do that in the modern world of modern production is MIM. For 99% of 1911 buyers these days it is not going to matter because the gun will never see enough rounds to shoot the mim parts to failure. There will be bad batches here and there that will fail at low round counts but that can happen with any manufacturing process. Consumers don't want to pay for quality they want it as cheap as they can and then complain that it breaks.

In reality if you are not going to to carry it or use it for self defense it does not matter. If the part breaks you can simply replace them with forged or bar stock parts. If you are carrying the gun you might consider replacing the parts or stepping up the food chain to a non mim gun from the start.
 
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IMHO MIM in 1911s is solely there to allow a company to met a price point. People want a $60o 1911 with all the bells and whistles right out of the box. The only way to do that in the modern world of modern production is MIM. For 99% of 1911 buyers these days it is not going to matter because the gun will never see enough rounds to shoot the mim parts to failure. There will be bad batches here and there that will fail at low round counts but that can happen with any manufacturing process. Consumers don't want to pay for quality they want it as cheap as they can and then complain that it breaks.

In reality if you are not going to to carry it or use it for self defense it does not matter. If the part breaks you can simply replace them with forged or bar stock parts. If you are carrying the gun you might consider replacing the parts or stepping up the food chain to a non mim gun from the start.


Truth!! ^^^^

MIM is what keeps most handguns at sub $1,000 price points.
 
A good MIM part, one that is dimensionally correct and has not been modified to remove its surface hardening, will be just as durable as any other, for all practical purposes. If you can afford to put 10,000 or 20,000 rounds of .45 through a 1911, you can afford a little PMCS with small parts replacements and fitting down the road. Nothing lasts forever, and guns should not be shot until something breaks outside of experiments. You wouldn’t drive a car long-term without replacing oil, filters, tires, brake pads, etc. Parts, even frames and slides, have schedules for long-term care/examination/refitting/replacement.

Cast, machined, and forged parts can have manufacturing defects and dimensional issues, and people were breaking gun parts long before powdered metal sintering.

If a slide stop is in a poorly fitted barrel and frame, it will fail (deform or crack) regardless of manufacture method. A poorly fitted firing pin stop will eventually crack, regardless of manufacture method. The only difference might be the time it takes for that failure to occur.

If the parts in your 1911 show regular wear/polish patterns and mate snugly in their respective positions, spend the money on ammo and worry about upgrades later. Some people do the upgrades early for piece of mind, which is fine (it’s America), but it should not be considered a “mandatory” component of owning and carrying a basic American-made 1911, even a less expensive one.

I trust the factory metallurgy in a modern Ruger or Springfield far more than in my 69-year old Colt.
 
Good MIM is quite good. Bad MIM is worse than junk. Quality is dependent on the material used and adhering to the correct process in making it.

In the applications it's suited for, it can outlast barstock. It does well with friction and compression, but not so well with shearing and impact stresses. Likewise certain tensile stresses.

A quick story.

Friend buys Billboard 1991A1 Colt. Brings it around with a new machined sear and disconnect and asks me to change his nasty old MIM parts.

Afterward, I arrange a little scientific demonstration.

Clamped the disconnect in a vise and gave a couple good whacks with a 4-ounce hammer. It bent to (estimated) 20 degrees before it snapped.

Laid the sear concave side down on the concrete floor and whacked it with the hammer. Not only did it not shatter, when I installed it in a gun, it still worked. Trigger pull was a little rough, but it worked.

One thing about MIM. Love it or hate it...it's here to stay.
 
A quick story.

Friend buys Billboard 1991A1 Colt. Brings it around with a new machined sear and disconnect and asks me to change his nasty old MIM parts.

Afterward, I arrange a little scientific demonstration.

Clamped the disconnect in a vise and gave a couple good whacks with a 4-ounce hammer. It bent to (estimated) 20 degrees before it snapped.

Laid the sear concave side down on the concrete floor and whacked it with the hammer. Not only did it not shatter, when I installed it in a gun, it still worked. Trigger pull was a little rough, but it worked.

One thing about MIM. Love it or hate it...it's here to stay.

Honest question: if a MIM disconnector is properly fitted into the gun (not excessively proud of or loose within the frame), and the firing pin stop and breach face bear an appropriate radius and small chamfer, respectively, would the capacity for the stem of that disconnector to withstand lateral shear load be an issue? The slanted faces should be hardened, and the gun should be at least somewhat lubricated, so the only real vector of force (translated from the slanted bearing surfaces) acting on the disconnector should be basically straight up and down... right?

Given that the gun was a Colt, and Colt’s QA for assembly/fitting small parts is... questionable... bar stock replacements are probably a decent idea. More asking, theoretically, whether a well-fitted MIM disconnector would be exposed to lateral shear forces in its ordinary function. You’ve probably been inside more 1911s than the armorers at the CMP. Thought I’d ask! I have another rebuild project going.
 
Diconnects...or any other part...in off the shelf pistols aren't fitted. They depend on being in-spec within acceptable tolerances. At most, a part may require "cherry picking" to drop in and function. When you get into oversized aftermarket parts, you'll probably need to do a little fitting.

Due to the angled surfaces on both the disconnect and the slide, there is little lateral or shearing force on the part.

I have two early 1991A1 Colts...bought in November of '91 and Februracy '92...that I acquired specifically for beater duty. Collectively, they've seen close to 400,000 rounds about evenly split. They're both on their 3rd barrels, and both were tightened up at around the 75.000 round mark to reduce the slide to frame vertical play. Both nylon mainspring housings were replaced at this time.

One is still running on its original sear and disconnect, and in the other, I replaced the disconnect...not because it failed, but because it was a little worn, and I wanted to apply the "Stitch in Time" philosophy as is my habit.

I also replaced the failed slidestop in one...a barstock part...with a cast slidestop from Ed Brown. Both still have their OEM magazine catches...both MIM parts. I also replaced both triggers because the factory units had a little too much slop for my tastes.

Small radius firing pin stops were installed as SOP on any new or new-to-me 1911 pistol.

Generally speaking, if an MIM part is going to fail, it will fail early. If it lasts for 500 cycles, it'll probably last for 50,000.
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The take away is to get a Glock.
No worries with MIM since it’s IM.


Glocks now have MIM parts.... They ( and all the others ) who use MIM parts use the MIM automated process for one reason...

To lower production costs....

If you shoot alot, keep an eye on your gear and keep it serviced. Run the MIM parts till they give up and replace with true machined parts... Easy deal!
 
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Glocks now have MIM parts.... They ( and all the others ) who use MIM parts use the MIM automated process for one reason...
To lower production costs....
If you shoot alot, keep an eye on your gear and keep it serviced. Run the MIM parts till they give up and replace with true machined parts... Easy deal!
I was attempting a funny, since most of a Glock is injection molded.
 
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