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Discussion Starter #1
How much tension are you guys using for your 9mm 1911's? I typically do something in the neighborhood of 25 oz with my 45's, but when I tensioned my 9mm Commander to that ejection got a little weak. I don't know if it's because the extractor is holding tighter to the empty case relative to the slower slide speed of the 9mm.
 

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Womb? Weary? He rests. He has travelled.
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9 mm extractors require different tension and geometry than .45acp extractors. If the extractor worked prior to your adjustment the hook may be engaging the brass at the wrong location.
At one time I believe there was a drawing showing the correct geometry and exactly where the hook was to engage the brass. I don't have it but someone may.
 

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Discussion Starter #3
The hook actually engages the brass at the extractor groove as opposed to the bevel in front of it. The hook to breech face distance looks really good. Before adjustment the ejection was stronger, but more erratic. Now it's more consistent, but weaker.
 

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Discussion Starter #6
Bradd_D, were you able to set deflection to .010" and were you able to get a hook-to-breechface distance of .060"?
The hook to breechface distance is very close to .060". How would I measure deflection for a 9mm where the edge of the hook grabs the case as opposed to the wall?
 

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Discussion Starter #7
One more thing to note is that with more tension I got a couple of failures to eject. With less tension, I've had no stoppages so far.
 

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One more thing to note is that with more tension I got a couple of failures to eject. With less tension, I've had no stoppages so far.
Be careful about assuming this has to do with tension.

Set the deflection as precisely as you can to .010" first then worry about tension.

In this specific example it's entirely possible that while the extractor is pulling the fired case out of the chamber, the next round in the magazine is actually doing the ejection of the fired case.

Depending on the length of the ejector the fired case may not actually be making it all the way to ejector. Instead it may be falling off the extractor and as the next round in the mag pops up under the feed lips it is smacking the empty case and kicking it out of the ejection port.

The entire process of fitting the extractor must be done methodically without skipping any steps. Otherwise, you'll have a tough time diagnosing the cause of any malfunctions like the one you just experienced.
 

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Discussion Starter #10
I need to figure out how to check deflection when I can't use the case rim as a reference since it never touches the extractor wall. The case is held by the edge of the hook.
 

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If you haven't already done so, take a look at my tutorial on extractor fitting.

First, the distance from the edge your extractor claw to the left guide block needs to be .010" less than the diameter of the bottom of the case extractor groove (CEG) + 1/2 of the rim diameter.

If you're very careful, you might be able to measure the distance from the claw to the left guide block using calipers.

If you have a file and some scrap material laying around you could make a gauge of the correct width. I've made gauges out of flat steel stock but since the gauge doesn't get any wear, you could make one out of plastic, wood, or even thick card stock (although it'll be a bit too delicate I suspect).

SAAMI spec for the 9mm CEG diameter is .347" -.020" (midpoint: .337").
SAAMI spec for the 9mm rim diameter is .394" - .010". (midpoint: .389").

We want the edge of the extractor claw to contact the CEG and we want the opposite side of case rim to be in contact with the left guide block.

So, if we use the midpoints and realizing we need to add half the rim diameter, we're looking at .363" - .010" = .353" as the ideal distance from the edge of the extractor claw to the left guide block.

I've never calculated this for the 9mm before but in my mind it makes sense. I'm going to do a CAD drawing to double check everything then I'll come back and either confirm that I'm a genius or eat crow and fix the numbers above.

EDIT: I just verified the .353" number by drawing everything out in CAD. I'll post a picture of it later. I am a GENIUS :laugh:
 

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1911 Pistol Smith
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I picked up this drawing sometime ago, and I believe it might have come from Steve's tutorial, or possibly something Brandon Bunker once shared.. I thought it was a pretty good rendition and sometimes a picture is worth 1000 words.. I for one, learn much more by doing than reading often times. But, when you combine the two it is much easier to see what your end result should look like. In this case the deflection is not measured off the pad as it is in the 45 but rather off the edge of the extractor claw and the contacting surface on the case. But, also as Steve mentioned in the instance of the measurement off of the left guide block you have to take into account that it is contacting the rim of the case and not the extractor case groove as mentioned. So that difference has to be accounted for as well.

So in reality my only contribution to this post is the picture ;) HA~~!!
1911 extractor Tuning.jpg
 

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Discussion Starter #14
So, I got some measurements with a caliper.

The extractor has about .005" of left to right play in it. With the extractor all the way to the left, the measurement is .348". With it all the way to the right before the tension comes into play, it is .353".
 

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Discussion Starter #15
While we're talking about all this, would I benefit from a longer ejector? I use Wilson ETM mags which have a rear spacer, if that matters at all.

IMG_3455.JPG
 

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1911 Pistol Smith
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There shouldn't be any play in the extractor, a little more tension may ensure the fitting pad is indeed pressed up against the extractor wall. .005 is not that much so it won't take much to remove the play.
 

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1911 Pistol Smith
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9mm ejector length according to prints is .316 from the center of the front pin to the nose of the ejector.. I never tune my ejector to this particular measurement, but start with a long nose and work back until I get the desired ejection position.. But, if you are close to the .316 you should be fine.
 

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Discussion Starter #18
9mm ejector length according to prints is .316 from the center of the front pin to the nose of the ejector.. I never tune my ejector to this particular measurement, but start with a long nose and work back until I get the desired ejection position.. But, if you are close to the .316 you should be fine.
It's definitely shorter than .316".
 

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1911 Pistol Smith
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It's definitely shorter than .316".
I thought it looked a tad short and could be the culprit of the erratic ejection patterns to begin with as the underlying round could be assisting in the actual ejection process. Did you try firing and ejecting rounds without the magazine.. Just one round at a time and observe it that way?
 

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Discussion Starter #20
I thought it looked a tad short and could be the culprit of the erratic ejection patterns to begin with as the underlying round could be assisting in the actual ejection process. Did you try firing and ejecting rounds without the magazine.. Just one round at a time and observe it that way?
I haven't fired it that way yet, but it won't eject an empty by hand cycling hard with no magazine. Next range session I'm going to try it live fire.

It will hold on to the empty all the way to the ejector when retracting the slide by hand.
 
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