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Discussion Starter · #1 ·
i bought my usp compact .40 used and it has been great, love the thing. would have bought new but couldn't afford it and no other gun has caught my eye like this one. anyway, after my last shooting session i did a field strip and clean. i was looking at my extractor and noticed that it's not squared off at the claw. it has a slant, which i've heard other models having and decided i needed to post this. i'm wondering if this is normal or if it's chipped? i've had no problems with it ejecting the round after being fired but just wanted to know.

i have however had 3 rounds fail to feed. the edge of the casing is catching on the edge of the feed ramp. i'm thinking it's the just cheap plinking ammo i'm using (blazer brass from wally's world). i have a few boxes of the 155gr. rangers i think i'll put through it along with some WWB's or something. they're mid mag rounds and not nose diving so i didn't think it was the mags (also happened in a new factory one).
 

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The extractor on my USPc .40 is the same. It starts out square at the top, then about halfway down it starts angling.

Must be to facilitate grabbing the case rim on feed.
 

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Discussion Starter · #3 ·
great news!!! it has some wear on it that must be from loading a round (not through the mag) and having the extractor hit against it. ah well, atleast it's not broken. i thought it was a little too smooth and machined looking.

anybody know anything about the FTF problem?
 

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i've got an another question regarding extractors.

i know in 1911s they say that it can be damaging to the extractor if you load a single round into chamber via the ejection port with the slide locked open and then release the slide. does this also holds true in HK USPs?

thanks
 

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Question has been asked many times

It's just not a real good idea to load a round in any simi auto and let the slide slam home.:26: Will it really damage the extractor that depends on the persons luck good or bad luck.:480:
 

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i've got an another question regarding extractors.

i know in 1911s they say that it can be damaging to the extractor if you load a single round into chamber via the ejection port with the slide locked open and then release the slide. does this also holds true in HK USPs?

thanks
From what I understand, yes. The extractors are made out of an extremely hard metal (the finish is flaking off mine, which I also understand to be normal) and are prone to chipping when slamming home the action on a chambered round. Always chamber from the magazine.

To the original question. Most extractors on autoloaders are milled at an angle. Completely normal.
 

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I've yet to understand why anybody would even think of loading through the extraction port directly to chamber. Makes absolutely no sense mechanically or in any other way. Just what gives this idea to people?????! :480:
 

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Discussion Starter · #8 ·
not to be a ****, but let's not turn this thread into one of those. there are quite a few and i think i remember seeing one 5+ pages long in my quest for pictures of the extractor.

anybody have any information on the FTF issue? probably just the ammo?
 

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The worn, uneven look of the extractor is perfectly normal. They all look like that straight out of the box.

The failures to feed are not normal and are most often caused by insufficient mag-spring pressure (replace mag-springs with Wolff +10% at www.gunsprings.com), or also by a dirty extractor. When gunk builds up behind the "tooth" or "claw", it interferes with it getting a good bite on the case rim.

You can test your mag-springs to see if that's the cause of the problem by stretching out one of the springs evenly so that it is about 2 inches or more longer than when you removed it, put it back together and test. If the increased pressure reduces or eliminates your problems, then you would benefit from a new set of Wolff springs. Keep in mind that stretching the springs that way will ultimately weaken them even more, so it cannot be considered a fix. They will revert within a mag or two of use.

The gunk behind the extractor tooth is sometimes hard to see because it hardens and starts to appear like black gun-metal. Hardened deposits can easily be removed with the pointed tip of a brass cleaning jag (do not use anything harder than brass), which will scrape away the deposits but not hurt the gun. You also need to check that the extractor moves freely with no grinding or binding. If not, then it must be disassembled for a good cleaning and lubrication. :)
 

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Discussion Starter · #10 ·
thanks for the reply orfeo. i was thinking of getting the wolff springs soon. i noticed that there was a little "gunk" behind the extractor claw and am wondering if that had something to do with it. i'll try cleaning that out first (though i definately want to replace the springs in the used mags). the only reason i'm thinking that it might not be the mags is because it happened with a new one. the extractor does move freely and there is no "grit" feeling and the spring feels tight.
 

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Reasons for loading through extraction port:

#1 I suppose some people load a snap cap through the extraction port and then release the slide.

#2 Load a round like this before putting a loaded mag in so you don't have to reload a mag for full capacity.
 

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The extractor does not snap over the rim during normal operation.

The wear on the forward face of your extractor is not from contact with the rim of the case but from contact with the "shoulder" between the extractor groove and body of the case. During normal operation, the rim of the case slides between the breach face and the extractor as a round is stripped from the magazine. The angle of the extractor discussed previously is a ramp which helps guide the extractor into the groove on the case. The photo below, not a great one though, shows that the extractor is already seated in the extractor groove before the round clears the magazine.



Furthering the education process, the round is held in line with the bore by the extractor as it is being fed into the chamber of the barrel. There is very minimal contact, if any, between ammuniton being stripped from the magazine and the feed ramp on the barrel which begs the question, why have one? My guess is it is a reliability issue in the event the extractor claw missed the groove when a round is being fed.

Witness marks in two areas support my opinion. The first area would be the right shoulder of the entrance to the chamber. This area counters the extractor pulling the round to the right as it is being fed into the chamber. The second is the bottom shoulder of the feed ramp which receives more contact from the "on deck" round during the firing cycle than the round being fed.

Manually feeding a round throught the ejection port is bad for your extractor under any circumstance.
 

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Discussion Starter · #13 ·
thanks for that informative post raufoss. so i guess i was wrong in my guess that somebody was loading incorrectly with it (still possible but not a positive).
 

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. . . i definately want to replace the springs in the used mags). the only reason i'm thinking that it might not be the mags is because it happened with a new one. . .
The fact that it happened with a new mag doesn't rule out mag-springs as the culprit. Several brand-new USPs with all new mags have been known to FTF due to insufficient mag-spring pressure. Lots of guys on here have had to replace their factory originals with Wolff within months or weeks of getting their new pistols. . .

Yes, I know it's BS and shouldn't happen with a brand-new HK, but the fact remains that it does happen to a small percentage of new HK pistol owners (including me!). Alot of guys on here just replace all their mag-springs with Wolffs as a preventative upgrade, even if they have had no problems with the original springs. :)
 

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Furthering the education process, the round is held in line with the bore by the extractor as it is being fed into the chamber of the barrel. There is very minimal contact, if any, between ammuniton being stripped from the magazine and the feed ramp on the barrel which begs the question, why have one? My guess is it is a reliability issue in the event the extractor claw missed the groove when a round is being fed.

Witness marks in two areas support my opinion. The first area would be the right shoulder of the entrance to the chamber. This area counters the extractor pulling the round to the right as it is being fed into the chamber. The second is the bottom shoulder of the feed ramp which receives more contact from the "on deck" round during the firing cycle than the round being fed.

Manually feeding a round throught the ejection port is bad for your extractor under any circumstance.
I'll respectfully disagree. IMO, the feed ramp is a critical part of the feeding process. As the round exits the magazine, it is not yet at the height of the bore axis, and depends on the ramp to correctly feed. The extractor function at this point is to hold the case head (loosely) against the breech face, preventing it from "wobbling away" and causing a misfeed, and not to hold it in line with the bore axis for a straight-in push by the breechface. If the extractor held the case in line with the bore axis, then there would be no marks on the feed ramp, ever. Every pistol I've ever shot (HK included) always has rub marks from the bullet nose on the ramp after firing. While I know HKs are not 1911s, think about the 1911 feed process for a minute...

The breechface strips a round from the mag, and the case head rides up under the extractor as the magazine releases the round. The underside of the bullet nose then bounces off the feed ramp, beginning the chambering process. The upper side of the bullet nose them bounces off the top inside of the barrel hood, guiding it into position. Finally, the breechface completes the chambering process by ramming the round fully into the chamber.

As for your witness marks, I say the mark on the right shoulder of the chamber entrance is caused by extraction, not chambering. If this mark were caused on chambering, then the feed ramp would be on the right, not on the bottom. The extractor does not "pull the round to the right" as the extractor has no lateral pull on the bullet at all (what you may be thinking of as lateral pull is the effect of the ejector on the case, and this only occurs when the case head is in contact with the ejector at the end of the full ejection cycle.

Second, the ramp marks cannot be caused by the "on-deck" round, as this round's nose is nowhere near the ramp, as can be seen in these pictures (barrel is positioned as it would be if the slide were in place)...





All of this can be verified yourself. Lock your slide back, insert a loaded magazine. Slowly ease the slide forward, looking through the ejection port, and watch as the bullet nose hits the feed ramp.
 
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