I'm going to agree with BB57, with ammo other than ball ammo and magazines that follow the original M1911 design, there can be more to it than a simple parts swap. Some fitting and adjustment may be required. USGI extractors are good quality as they were made according to the original design specification, specifically, the use of a spring tempered steel. Modern and replacement extractors are MIM, cast steel, or machined from bar stock. The alloy used and the heat treatment will determine the durability of the extractor. I do not think that MIM nor cast steel alloys would make for good candidates for the tempering that creates spring steel. Wilson, EGW, Cylinder & Slide, and Ed Brown usually get high marks for quality.

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VCDL, GOA, NRA