Rimfire internal ballistics

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jwax

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Question: Why is an extractor needed, for example, in a S & W Model 41, when the spent brass is blasting back the slide anyway?
Isn't the pressure pulse driving the brass into the face of the slide, pushing the slide back, meaning the brass is self-ejecting anyway? Why an extractor claw is needed is puzzling me. What am i missing here?
 
its for when you dont fire, yet want to extract
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Bingo. In the shop where I worked many moons ago...a guy walks in with a semiauto .22 rifle. He yanks the bolt 2-3 times to show that it's empty...lays it on the counter. Guy behind the counter repeats the bolt yank. First guy says not to worry that he already checked it. Second guy opens the bolt again and looks into the breech and sees the shiny butt of a live rimfire cartridge smilin' at him. Sometimes they don't fall out...

The reason that the guy brought the rifle in? You guessed it. Failure to extract. Diagnosis? Broken extractor. Gimme a D! Gimme a U! Gimme an H! Whattaya got? DUH!

The extractor also holds the empty case against the breechface so that the ejector can take a solid whack at it and kick it clear of the breech. There are some few blowback .22 pistols that don't have an extractor. Notably the old Beretta tip-barrel autos, and they seemed to work prettywell...but I much prefer an extractor on my guns.
 
The OP is correct - in a blowback pistol, an extractor is not needed to extract the fired case, it blows itself back out of the chamber, which is why the action is called "blowback".

But the extractor might, depending on the design, be necessary as a pivot point for the ejector. As far as I know, the Beretta and others without extractors were all tipups, so the end of the barrel could be exposed and a live round or a misfired round could be removed with the fingernail.

Jim
 
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