Let's make certain that we're talking correct terms...
The receivers are NOT metal injection molded, in which powdered metal is put into a form and then subjected to extreme pressure.
In the sintering process apparently used by Winchester, powdered metal is put into a form, which is then heated to melt the metal. At least I think that's the process that Winchester used.
That kind of sintering process allows very precise control of additives to the metal powder, giving the finished product the exact properties that they want.
Apparently the process is faster, and cheaper, than the traditional method of milling from a billet of steel.
It's SORT of like casting in that both use forms.
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