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Really appreciate your thread on extractors. Just curious if you have any extractor data for use in 9's and .40's? Do you still use .010 deflection ? How big should the gap between hook and breechface be? Stuff like that. Maybe you could do an addendum to your thread about extractors? Anyway, would appreciate any info you could pass on. Was gonna pm you, but figured there'd be other people besides me that would appreciate your expertise. Thanks.
Bob
 

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Really appreciate your thread on extractors. Just curious if you have any extractor data for use in 9's and .40's? Do you still use .010 deflection ? How big should the gap between hook and breechface be?
The concept for fitting internal 1911 extractors is the same across all calibers. The major differences include hook-to-breechface distance and whether or not the claw contacts the case.

Here are the optimum hook-to-breechface distances provided by log man:

  • 9mm - .060"
  • 40 S&W - .065"
  • 45 ACP - .075"

The reason for the differing distances has to do with the differences in rim diameters and the angle at which the cartridges feed. It is important to note that no extractor in any caliber should contact the case bevel.

Optimum deflection across all calibers remains .010".

As for the claw contacting the case, they should never touch a .45 case except, of course, after the round is fired and the extractor pulls the empty case out of the chamber. Even then the only area of the extractor that should make contact with the case is the rear face of the claw.

Most 9mm and .40 extractors are fitted so that the edge of the claw bears against the flat area just ahead of the rim but before the case bevel. For these extractors the case rim doesn't contact the extractor's tensioning wall like a .45 extractor.

Fitting a 9mm or .40 extractor exactly like a .45 is more difficult than just allowing the edge of the claw to bear against the case. It can be done and is probably the ideal way to do it but few do it this way.
 

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After reading Steve's original extractor discussion I thought my Ruger SR1911 LW CMDR's extractor was fitted wrong. The claw is pressing on the groove. But now I see that this is in fact the way it should be.


My SR1911 is new with only about 100 rounds of hardball and 20 rounds of hollowpoints through it. But I've had occasional FTF where the cartridge doesn't go all the way into the chamber. Its stops maybe 1/4" short of battery. A bump on the rear of the slide sends it home. With the barrel removed, a loaded cartridge drops cleanly into the chamber with no hang ups. It seems to pass the shake test where it holds with gentle to moderate shaking, but with hard shaking it will eventually come out. But I'm thinking that the tension may be a little too tight. Here is what mine looks like. I'd appreciate thoughts on what to do with the extractor, if anything. Thanks.
 

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The claw is pressing on the groove. But now I see that this is in fact the way it should be.
If your pistol is a .45 then no, that's not the way it should be. If it's a 9mm then it can be that way or it can be fit like a .45.

As you say, the feeding problems you're having are most likely related to the extractor. If you wish the extractor to continue contacting the case as shown in your picture, all you need to do to fix the feeding problem is follow the concepts in my sticky.

Make sure the edge of the claw is smooth and not digging into the case.

Set the deflection to .010". Measuring the distance the edge of the claw moves outboard as the cartridge slides up the breechface might be a trick. I'd be interested to know the technique folks use to do this.

Set the tension.
 

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Sorry, its 9mm. I did gently round the lower corner of the claw to help the case ease under the extractor. To set tension, maybe I can make a gauge that is .010" smaller than the average case groove size. I'll need to think about that....
 

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I think your idea for a gauge is spot on.

From a closer look at your picture it looks like the claw will impact the case bevel and not allow the base of the case to be pushed back flush against the breechface. You don't want this. You can either buy a new, shorter extractor, relieve the front of the claw so that it doesn't impact the bevel, or work on the extractor's firing pin stop slot to pull the extractor back enough to clear the case bevel.

Relieving the front of the claw is an acceptable method as long as it's not overdone. Taking too much material off will weaken the extractor and may result in the hook breaking off. I can't tell you how much is too much. It's a judgement call.
 

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To set tension, maybe I can make a gauge that is .010" smaller than the average case groove size.
To be perfectly clear, the gauge does not allow you to set the tension. It allows you to set the deflection.

Deflection is the most misunderstood, most often ignored, most difficult, and most important (IMHO) factor in setting up an extractor.
 

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To be perfectly clear, the gauge does not allow to to set the tension. It allows you to set the deflection.

Deflection is the most misunderstood, most often ignored, most difficult, and most important (IMHO) factor in setting up an extractor.
Yes, I chose the wrong word. I'll try to go to the range in the next day or so and see if what I did so far make any improvement. If not, then I'll try to lighten the tension a tad and see if I can make a deflection gauge. Thanks for all the advice!
 

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What about .38S. I found that since the length of the case is longer than a 9mm the space needs to be greater than .060” or you get rim bite.
 

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Sounds like someone on this forum should make some high quality deflection gauges. I would buy a set, and I bet there are plenty of others as well.
 

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Sounds like someone on this forum should make some high quality deflection gauges. I would buy a set, and I bet there are plenty of others as well.
They can be made out of nearly any material since they don't get any wear and tear. I suggested to George Smith (EGW) the idea of making them out of plastic using a 3D printer and selling them as a set covering a range of widths in .001" increments. They'd be cheap to make and as long as they could be made in precise widths they'd be profitable. He didn't show any interest.
 

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What about .38S. I found that since the length of the case is longer than a 9mm the space needs to be greater than .060” or you get rim bite.
A very interesting question. Maybe someone with more .38 Super knowledge than I can weigh in.

Here are the SAAMI specs for three cartridges:

.38 Super - case length .900", rim diameter .406"
.45 ACP - case length .898", rim diameter .480"
10mm - case length .992", rim diameter .425"

If I had to guess, I'd say the .38 Super hook-to-breechface distance would be would be somewhere around .70".
 

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Why would case length matter? Rim thickness from base to extractor grove should be the determining factor.
Joe
 

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Why would case length matter? Rim thickness from base to extractor grove should be the determining factor.
Joe
Here are the optimum hook-to-breechface distances provided by log man:
  • 9mm - .060"
  • 40 S&W - .065"
  • 45 ACP - .075"

Here are the SAAMI specs for rim thickness from base to extractor groove:

  • 9mm - .050"
  • 40 S&W - .055"
  • 45 ACP - .049"

I'm not seeing the correlation between rim thickness and hook-to-breechface distances. That distance may be more of a function of the angle at which the rim begins moving up behind the extractor. That angle would be influenced by the length of the cartridge. I'm just speculating here. Where are the engineers when you need them?
 

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Why would case length matter? Rim thickness from base to extractor grove should be the determining factor.
Joe
Here are the optimum hook-to-breechface distances provided by log man:
  • 9mm - .060"
  • 40 S&W - .065"
  • 45 ACP - .075"

Here are the SAAMI specs for rim thickness from base to extractor groove:

  • 9mm - .050"
  • 40 S&W - .055"
  • 45 ACP - .049"

I'm not seeing the correlation between rim thickness and hook-to-breechface distances. That distance may be more of a function of the angle at which the rim begins moving up behind the extractor. That angle would be influenced by the length of the cartridge. I'm just speculating here. Where are the engineers when you need them?
Exactly, the longer the case or fatter, the more room needed for the rim to articulate into position behind the extractor hook.

IME The rim doesn’t just pop straight up parallel with the inner face of the extractor hook, they have to rotate up into position somewhat. Longer the case and bullet or fatter in diameter, the more room for articulation into place. I use .068” at least with .075” working just fine for .38S with the appropriate extractor hook shape and don’t get any rim bite, anything smaller and the rim gets chewed up a bit.
 

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Why would case length matter? Rim thickness from base to extractor grove should be the determining factor.
Joe
Here are the optimum hook-to-breechface distances provided by log man:
  • 9mm - .060"
  • 40 S&W - .065"
  • 45 ACP - .075"

Here are the SAAMI specs for rim thickness from base to extractor groove:

  • 9mm - .050"
  • 40 S&W - .055"
  • 45 ACP - .049"

I'm not seeing the correlation between rim thickness and hook-to-breechface distances. That distance may be more of a function of the angle at which the rim begins moving up behind the extractor. That angle would be influenced by the length of the cartridge. I'm just speculating here. Where are the engineers when you need them?
Exactly, the longer the case or fatter, the more room needed for the rim to articulate into position behind the extractor hook.

IME The rim doesn’t just pop straight up parallel with the inner face of the extractor hook, they have to rotate up into position somewhat. Longer the case and bullet or fatter in diameter, the more room for articulation into place. I use .068” at least with .075” working just fine for .38S with the appropriate extractor hook shape and don’t get any rim bite, anything smaller and the rim gets chewed up a bit.
Just to add to the confusion, I believe that our departed master smith, Jerry Keefer, used something around .067-.068 for .45ACP on his builds. I know, I know. Don't compare his builds to anyone else's. They were engineering masterpieces.
 

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Sounds like someone on this forum should make some high quality deflection gauges. I would buy a set, and I bet there are plenty of others as well.
I've made several sets folks on this forum and the other. Let me know what calibers and I'll make some for ya. I use O1 drill rod. Machines easy

Sent from my SM-N950U using Tapatalk
 
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