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Old June 17, 2002, 02:17 PM   #1
Charlie Rock
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Join Date: June 11, 2002
Location: Midland,Texas
Posts: 5
Advise on external extractors

I own a Star M-43 Firestar 9mm that I bought used some years ago. I noticed that the firing pin indentions in the spent primers were being smeared to one side as though the firing pin was still protruding from the breech face as the barrel was ramping down.

This was about the time there were articles in the gun mags concerning similar smeared primer indentions found in guns chambered for the then new 40 S&W. It was speculated at the time that manufacturers still had not perfected the timing for the 40 caliber.

I wrote to the NRA technical staff and asked their opinion of the cause of the smeared indentions in my Firestar. I received a very nice reply that stated the most probable cause was a weak recoil spring.

I only recently got around to ordering a new Wolfe recoil spring which also included a new firing pin spring. I have shot one box of UMC 115 gr ball with the new springs installed. The primer indentions are now perfectly round with no sign of smearing. Great, one problem solved.

But out of that one box, I had 3 failures to eject, with the spent case left 3/4 out of the chamber and the next live round jammed up against the bottom of it. The extractor is being pulled out of the extractor groove of the empty case. The question is why?

The pistol has failed to eject in the past so I was hoping the new recoil spring might slow the slide cycle down and allow the ejector to stay with cases better, but evidently not.

I'm familiar with fitting the internal extractor in a 1911 style pistol. The rim of the case is held by tension against the rim slot cut in the extractor. The hook of the extractor does not touch the case in the extractor cut, but only the rear face of the hook contacts the front face of the case rim during the extraction cycle.

The Star external extractor is just the oposite. The rim of the case has major clearance with the cut in the extractor. The case is held by the tension of the tip of the extractor hook against the bottom of the extractor cut in the case. Are all external extractors designed to apply tension to the case in this fashion? I've never found anything written on how to proberly fit or tune an external extractor for maximum reliablility. The extractor spring tension is more than sufficient to securly hold a live round against the breech face.

The extractor tip is very long and it would take major surgery to remove and reshape the tip to allow the case to be held only by the rim as would be correct for the 1911.

It might be dificult to find a replacement extractor, though I haven't research it yet. So I'm interested in any information you guys might have on the correct tuning of a external extractor and a possible source for a new extractor to fit the Firestar 9mm. I'm sure someone has had a pistol with an external extractor that failed to extract and found a cure.

Many Thanks, Charlie
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Old June 17, 2002, 09:50 PM   #2
James K
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Join Date: March 17, 1999
Posts: 24,383
Actually, it is the Model 1911 (type) that is the exception. Most extractors work just like the one on the Star.

Take a look at the empty cases. It could be that the chamber is rough and the case sticking, which would be indicated by the extractor pulling over the case rim. Does the rim show signs of being distorted by the extractor? The extractor hook could also be bent forward slightly or worn, allowing it to ride over the rim.

If case sticking is indicated, you might try polishing the chamber, using a strip of 600 grit emery paper in a slotted cleaning rod tip and a hand drill. Take it slow, though; you want only to polish, not grind.

I think it was the new firing pin spring that solved the firing pin drag, not the recoil spring. You might try going back to the old recoil spring.

Jim
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