Extracting Fired Cases
Removing a “smoking hot” fired .45 ACP case from a 1911 chamber which has just contained 18,000 to 20,000 PSI is quite a feat for a little piece of metal with a .032″ hook on its end. The extractor accomplishing this feat is one of the most misunderstood parts of the semi-auto pistol. Remarkably, it’s one of the few “modern” extractors that retain geometry and engineering devised well over a century ago — but it’s still effective.
The majority of pistol extractors in today’s autos are coil spring-driven and are designed for positive feeding, just like the extractor in the 1911. Positive feeding is when the cartridge slips up under the extractor hook as it’s stripped from the magazine, and the breech face moves it forward into the chamber. Coil spring-loaded extractors, such as used in Springfield XDM models, Glocks, M&Ps and others, are unique in they not only aid positive feeding, but can “snap-over” a cartridge already in the chamber without breaking the tip of the extractor — not so with the 1911 extractor. If the 1911 extractor is forced to snap-over a loaded or empty case in the chamber, you do run the risk of breaking the tip of the extractor off, rendering the pistol a single shot.
An untuned 1911 extractor can be a major source of feeding problems — yep, that’s right, feeding problems. In order to accomplish perfect, positive feeding, the cartridge must be stripped from the magazine, moved up the surface of the breech face, press the extractor tip back and smoothly slide under the extractor hook. Now here is where a major problem rears its ugly head. If the front tip of the extractor touches the front of the extractor groove on the cartridge case it will slow down the recoil-generated feeding cycle and potentially cause a malfunction. This type of extractor is easy to diagnose by examining your fired cases.
If there is an indentation or mark on the front of the case extractor groove, the nose of your extractor needs to have metal removed at about a 45-degree angle, enough to allow the extractor nose to clear the front of the extractor groove. Correcting this problem will assist a clean, fast reload from the magazine.
Another little tuning chore you should accomplish to facilitate positive feeding is to bevel the bottom of the extractor hook to about 45 degrees, which will keep the sharp corner from cutting into the rim of the cartridge as it moves up and under the extractor hook. Polishing the bevel and the bottom of the hook will also facilitate smooth feeding, even if the case rim is a little rough.
By Alex Hamilton
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