Switch out MIM parts

badkarma6

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Has anyone switched out the MIM parts on their revolvers for the case hardened trigger and hammer? Reason I'm asking is I recently purchased a 619, and I prefer the anesthetics of the case hardend parts to the stainless.
 
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Beyond esthetics and the ability to stone sear and engagement surfaces, forged parts have no advantage over MIM. MIM parts tend to have smooth and consistent surfaces, whereas forged and machined parts might be smooth or they might have rough engagement surfaces, depending upon the condition of the cutter.
 
I swapped out most of the MIM parts in one of my 686s several years ago and while I enjoyed doing it and I'm very happy with the end result (which includes an Apex bobbed hammer, power custom trigger, etc.) I'm pretty sure that I could've achieved a similar outcome with the stock parts so I'm not sure that I could justify the cost...

xReFm0i.webp


Also, the following is a very interesting 3 part article by Revolver Guy that changed my opinion quite a bit...

All About MIM–Part Three – RevolverGuy.Com
 
337,

That’s a handsome revolver, appreciate the way you dealt with the lock! Really like the rear sight as well. Bet that’s a good shooter - it just has to be…
 
I have not. I think too much emphasis is placed on old style parts vs new parts.

As someone said, the MIM are pretty precise and work. With the issues that do crop up on current production guns, can you imagine if they actually had to fit more parts by hand these days...
 
Just like Kelly Johnson said.....

337,

That’s a handsome revolver, appreciate the way you dealt with the lock! Really like the rear sight as well. Bet that’s a good shooter - it just has to be…

...about airplanes. If they look good. they fly good. If a gun looks good, it shoots good. But of course some ugly guns shoot good, too.:)
 
I thought about it, including installing an aftermarket stainless hammer and replacing the lock, but it's hundred of dollors in extra cost and possible fitting and other issues all for nothing other than looks and diminishing returns. I've settled on leaving well enough alone. Plus, in my humble and logical opinion, it's more cost effective to sell off 619 and simply buy a prelock no MIM Smith.
 
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I thought about it, including installing an aftermarket stainless hammer and replacing the lock, but it's hundred of dollors in extra cost and possible fitting and other issues all for nothing other than looks and diminishing returns. I've settled on leaving well enough alone. Plus, in my humble and logical opinion, it's more cost effective to sell off 619 and simply buy a prelock no MIM Smith.

Aa with your own body - the original architect knows more than any after market engineers.
 
Nothing wrong with well made MIM parts ( other than losing the nice case colors). As others have said, QC is important. I wish the 1911 world would get this thru their heads. When I got a Springfield 1911 there were lots of "Nice gun, remove all the MIM and replace with CNC parts"; my response was why, there is a lifetime warranty and if a part actually breaks they'll fix it so why pay a few hundred or more dollars for parts and labor that add if anything little to reliability.
 
Nothing wrong with well-made MIM parts ( other than losing the nice case colors). As others have said, QC is important. I wish the 1911 world would get this thru their heads. When I got a Springfield 1911 there were lots of "Nice gun, remove all the MIM and replace with CNC parts"; my response was why, there is a lifetime warranty and if a part actually breaks they'll fix it so why pay a few hundred or more dollars for parts and labor that add if anything little to reliability.
And then, if they ever sell or trade the gun, they're not going to recoup their investment. I have lost count of how many Glocks, 1911s, AR15s, Sigs, and other handguns that sit on ArmsList, Gunbroker, and on consignment because the seller thinks they can get, for example, $1500 for their $400 Gucci Glock Gen 3 because that added a bunch of "upgrades" that no one is willing to pay for.
 
As I understand it, you can swap triggers between old style (forged) and new (MIM) but not hammers. This is due to the frame mounted (new) vs hammer mounted (old) firing pins.

Do I have that right?

The only reason I personally would do this is to replace a damaged old style trigger with something readily available.
 
I am under the impression that MIM parts are hardened all the way through ,Not like forged hammers & triggers. that have to be case hardened

Not all MIM is hardened through. Pratt & Whitney has a proprietary process that hardens MIM parts all the way through with very precise dimensions. P&W makes the MIM parts for Colt…no idea whether that’s an exclusive deal or not.

Not all MIM is equal.
 
As I understand it, you can swap triggers between old style (forged) and new (MIM) but not hammers. This is due to the frame mounted (new) vs hammer mounted (old) firing pins.

Do I have that right?

The only reason I personally would do this is to replace a damaged old style trigger with something readily available.
I replaced an old style serrated target trigger with a newer style (mim) trigger. The old style is not really suitable to me for DA shots. And on a 44 magnum, on the heavier loads, the top part of the older style serrated trigger always rubs me wrong.
The newer mim trigger is much better designed for DA shots and SA magnums. To me at least.

Going from a 629-4 to an mim trigger, you'll need the "trigger lever" and the "hand torsion spring". I was able to re- use the old hand and keep the timing.

If my 629 was a -5. Even the hammer would have been replaceable with another mim hammer with no fitting involved.
 
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