Practical 1911 Extractor 9 / 38 / 40 Series 70 Blue will not work with the Schwartz (Kimber) style safety.
The steel available to us today is of much higher quality than what was available in 1911 when the 1911 pistol was first produced. Improvements to the entire manufacturing process include better alloys, more controlled furnaces, vacuum heat treat, better tooling, and finite element analysis-all of which we use in production.
EGW-specific Improvements to the original 1911 Extractor:
We found that the extractor rides up the relief groove on the ammunition casing with each round fired: this dulls the hook from constantly banging the case, over time tension is lost, leading to a jammed case which adversely affects accuracy. If you experience a loss of tension or must continually retension your extractor, it is time to replace it.
We fixed all 3 of these problems by reducing the distance from the bolt face to the extractor hook.
We found that most hook designs are cut straight at a right angle. We machined ours at an acute angle so that there is more surface area for the hook to bite into the case. Right angles are a weak point on other extractors so we put radii on both sides of ours to increase strength. The hook is machined with a special cutter that leaves a nice clean radius in the inside corner where most extractors fail.