Well anyone who has been a fan or owns a 1911 knows about Metal Injection Mold parts. MIM stands for Metal Injection Molded. In a cast part the metal would be poured and then sets up by itself. Its is very common place to find said parts in not just 1911 but almost all guns.
In Injection molding the molten metal is pressed into a mold at high pressure and then it sets inside the mold under pressure until it is of the strength specified to produce the given part. The grain structure is also controlled by the amount of pressure, usually in 10's of ton's per Sq. In. The pressures cause crystalline structure alignment of the atoms. It is the same process as most any plastic injection molded part..
Also, a big factor is the application for the MIM parts. Colt used MIM extractors in their 1911's until they found that this cost saving measure was not saving them money because of all the repairs they were doing on replacing the extractors under warranty. They stopped using MIM extractors but still use MIM parts for the mag release latch, sear, and some other parts. MIM parts can give you a very nice, smooth trigger as they are hard.
It is true that the most important factor with MIM parts is application of those parts (fine in ultra high speed jet turbine blades which do not flex but very poor application in firearm extractors which do flex-something Colt learned the hard/expensive((as in warranty repairs)) and the quality of the manufacturing process (questionable from a third world company).
So what do you prefer or what are your thoughts on this. If given the ability I would change all MIM part on my weapons to forged/machined from billet. I feel better knowing I have the strongest parts available, its just one less thing that could go wrong and it gives me piece of mind. I just like 100% metal machined parts.
In Injection molding the molten metal is pressed into a mold at high pressure and then it sets inside the mold under pressure until it is of the strength specified to produce the given part. The grain structure is also controlled by the amount of pressure, usually in 10's of ton's per Sq. In. The pressures cause crystalline structure alignment of the atoms. It is the same process as most any plastic injection molded part..
Also, a big factor is the application for the MIM parts. Colt used MIM extractors in their 1911's until they found that this cost saving measure was not saving them money because of all the repairs they were doing on replacing the extractors under warranty. They stopped using MIM extractors but still use MIM parts for the mag release latch, sear, and some other parts. MIM parts can give you a very nice, smooth trigger as they are hard.
It is true that the most important factor with MIM parts is application of those parts (fine in ultra high speed jet turbine blades which do not flex but very poor application in firearm extractors which do flex-something Colt learned the hard/expensive((as in warranty repairs)) and the quality of the manufacturing process (questionable from a third world company).
So what do you prefer or what are your thoughts on this. If given the ability I would change all MIM part on my weapons to forged/machined from billet. I feel better knowing I have the strongest parts available, its just one less thing that could go wrong and it gives me piece of mind. I just like 100% metal machined parts.
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