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Discussion Starter #1 (Edited)
We constantly get questions about extractors and ejectors on "blow back" operated guns like almost every 22LR pistol or rifle I have ever seen. So I am posting the general information on the topic.

To start with blow back operated guns do not use the extractor to extract the empty case during firing. The case self extracts itself from the chamber. In fact, the gas pressure pushes the case out of the chamber and the case acts as a piston against the bolt face to move the bolt or slide to the rear. The job of the extractor during firing is to hold the empty case tightly against the bolt face, even when the case has cleared the chamber, so that the ejector can hit the case and fling the case out of the chamber area in a controlled direction.

When manually clearing a gun chamber of a loaded round, the extractor does pull the round out of the chamber unless the gun is a break open gun like the small Beretta pocket 22 pistols. In those guns you are expected to dig the loaded un-fired round out of the chamber with a finger nail or tool. Remember, this is clearing the gun manually of a loaded round.

The shape of the extractor is critical. If wrong it may drop the empty case in to the chamber area and jam the gun. There are several criteria it must meet. Some are created by design and others made through proper fitting of the extractor.

For the first design feature, the extractor must have its center of mass positioned so that the action of the bolt going to the rear locks the ejector down harder on the case rather the allowing the extractor to loosen its grip. The second design feature (or can be achieved by fitting) is the nose of the extractor needs to be shaped so that the extractor hook is lifted off the rim as the cartridge fully seats in the chamber. There is a slot on the extractor side of the barrel that pushes against the nose of the extractor to assure the extractor disconnects from the case rim.

(continued in Part 2)

LDBennett
 

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Discussion Starter #2
Re: Extraction/Ejection in 22's, Part 2

(Continued)

The extractor needs to be fitted to the gun so that only the point of the hooked end of the extractor touches the case. In fact, that point of the extractor must only touch the case at the junction of the case rim and the case body and no where else. The bottom of the extractor hook must have a very slight chamfer so that as the rim of the case rises out of the magazine, the rim has an easy entry under the extractor.

There must be enough of a spring force on the extractor, with free movement on its pivot point in the slide or bolt, to assure the cartridge is held firmly enough so that the case does not drop off the bolt face until the ejector hits it.

The test for this later function is to remove the slide or bolt from the gun. Slide a loaded round up and under the extractor, fully seating it vertically on the bolt face. Now gently shake the bolt and the loaded round should not fall off the bolt face. Remember to inspect the extractor to see that only the point of the extractor is touching the case and then only at the junction of the rim and the case body and no where else. Fit the extractor, clean the extractor spring cavity and pivot point to assure this is all correct. Normally if the gun passes this test and the inspection then the added violence of firing a cartridge will not upset the function of the extractor. It should go without saying that there should be no burrs or deformation on the operating surfaces of the extractor or in the slide cavity for the extractor or in the extractor slot in the breech end of the barrel.

The ejector must be positioned in the gun so it strikes the case that is held to the bolt face during recoil. It must not drag on the slide as that might slow the gun's recoil action and affect the feeding of ammo out of the magazine. It must not be broken off such that it can not reach the rim of the empty case held to the bolt face. It must be "aimed" so that the case exits the gun, when hit by it, without hitting anything else in the chamber area of the gun.

Hope this helps.

LDBennett
 
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