January 10, 2019, 11:24 PM | #26 | ||
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Some CRF rifle designs don't have enough room in the action, and/or enough flex in the extractor, to allow snap-over. Forcing snap-over in those designs WILL damage the extractor. It's not a "maybe ... eventually". It is WILL damage, right now. Quote:
Which is more likely to cause injury that you prefer to avoid? (I have chosen the option of a potentially broken extractor over hand and facial injuries.)
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January 10, 2019, 11:40 PM | #27 | |
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Know the status of your weapon Keep your muzzle oriented so that no one will be hurt if the firearm discharges Keep your finger off the trigger until you have an adequate sight picture Maintain situational awareness Last edited by TunnelRat; January 10, 2019 at 11:57 PM. |
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January 10, 2019, 11:49 PM | #28 | |
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Bullet setback is a real thing, but in normal quality ammo it is not a major concern unless you repeatedly (more than 2 or 3 times) load and unload the same round. And almost every round WILL hit the feed ramp anyway?
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January 11, 2019, 02:16 AM | #29 | ||||||
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I own a few semi-auto pistols that are designed to tolerate direct chamber loading according to the manual. Glocks are not. In Glocks, the practice can chip the extractor. Simple solution. Unless the manual or the manufacturer says it's an approved practice, chamber only from the magazine. At the very least, don't let the slide slam home from all the way back when direct chamber loading a gun that's not designed for it. Only pull the slide back just enough to let it snap over the rim. Quote:
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In extreme cases, a tenth of an inch of setback can double the discharge pressure. That's a real problem. Premium ammunition with brass cases will not setback from a single chambering, or even several chamberings. I seem to recall that at one point I found some information somewhere from one particular manufacturer stating that their premium ammo should tolerate 4 chamberings without setting back. But eventually, the slamming will break things loose and the bullet will start to setback. Fortunately, there's a simple solution. Don't keep rechambering the same round over and over. And if it's cheap practice ammo, especially with aluminum casings, chamber it only ONCE. I have seen ammo that would setback from being chambered once. It was bargain practice ammo with light bullets loaded in aluminum cases and the loading was pretty mild. So I didn't have a problem shooting it--but you can bet I didn't rechamber ANY of that ammo. Once it got into the chamber, it was either fired or discarded. Quote:
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It might be reasonable to make the claim that: "In your opinion, every gun you have ever seen appears to be designed to allow the extractor ride over the rim of the cartridge without damage." Implying that you know with a certainty how the extractor system of every gun you've ever seen was designed to operate is just not remotely credible. Anyway, unless you've never seen a Kahr, the statement is false. The Kahr P9 manual tells the user: "Do not load an individual round into the chamber and then close the slide. This can damage the extractor. Only chamber rounds from the magazine as described..." Clearly there are pistols that are not designed to have the extractor ride over the rim of a cartridge.
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January 11, 2019, 04:15 AM | #30 |
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I know nothing about Kahrs, obviously.
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January 11, 2019, 11:27 AM | #31 | |
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All brands and quality levels of ammunition can suffer bullet setback. Whether due to the manufacturer's loading practices, a quality failure, or negligent repeated chambering by the end-user, they can all suffer setback. The most recent examples that I've setback with were Hornady Critical Defense 90 gr FTX .380 Auto, Speer 124 gr Gold Dot LE 9mm, and Barnes 115 gr TAC-XPD. It happens with rifle ammo, too - and setback doesn't even have to happen inside a firearm. About two months ago, I dropped a factory Remington .300 Blk 220 gr OTFB subsonic load on a concrete floor. It landed base-first. When I picked it up, the cartridge overall length was more than 0.150" shorter. I don't think anyone would classify any of the above as "low quality." Yet, they all suffered from bullet setback with minimal or single chamberings (or one drop). Some people snap-over. Some people don't. Some people wipe front-to-back. Some people wipe back-to-front. Some people do both. It's a personal choice. (Just don't wipe side-to-side. That's not good for anyone.)
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January 11, 2019, 05:18 PM | #32 |
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I think. That with the Beretta 92 series, that you can load a single cartridge that way.
Seems I even saw that in this thread here somewhere.????? |
January 11, 2019, 06:54 PM | #33 |
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Regardless, most guns are designed for the extractor to slip over the rim of a chambered cartridge. That's why they are sprung.
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January 11, 2019, 07:32 PM | #34 | |
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Kahr states in their manuals that one should not "slingshot" the slide to chamber a round, but instead release the slide stop to load from a magazine. In fact, I've seen on many forums that many will not purchase a Kahr arms pistol for this very reason, thinking that this would not be good from a defense pistol viewpoint, i.e with a closed slide, and empty chamber you would have to first LOCK BACK THE SLIDE, and then release the slide on the magazine to chambe the round versus simply inserting a magazine and racking the slide. But on both my Kahrs, a K40 and PM9, they work just fine with an overhand "slingshot" as long as you don't ride the slide forward. In general, lots of stuff in owners instruction manuals are written by lawyers, not technicians.
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January 11, 2019, 07:43 PM | #35 | |
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January 11, 2019, 11:41 PM | #36 | |
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Not so sure about that. Last edited by Rinspeed; January 12, 2019 at 09:47 AM. |
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January 12, 2019, 12:05 AM | #37 | |||
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I don't think it's true that "most guns" are designed to tolerate that, and clearly, based on the Kahr example, whether they are beveled on the face or "sprung" isn't a reliable way to make the determination. If you have some other evidence to support your assertion, I would be interested to hear it. Quote:
HOWEVER, it is absolutely NOT true that chambering a round a single time will setback properly manufactured, good quality ammunition sufficiently to be dangerous. It doesn't even require a lot of thought or careful consideration to realize that good quality, properly manufactured ammunition can safely be chambered and fired. It is also not true that all ammunition WILL setback even a small amount from a single chambering--in my experience the ammo that will set back from one chambering is in the small minority. In addition, when we do see setback from a single chambering, the fact that there's measureable setback from a single chambering does not automatically imply that there's a dangerous situation. The setback needs to be significant, not just detectable. A detectable amount of setback from one chambering DOES, however imply that ammunition like that should NEVER be chambered more than once. What I stated was correct. "If you have ammunition that is setting back enough from a single chambering to be dangerous, then you need to contact the manufacturer and get your money back rather than adopting non-standard loading practices to try to compensate for the extreme lack of quality in the ammunition. Good quality ammo is safe to chamber normally and fire. Period. There is no need to direct chamber load to avoid setback with good quality ammo. Period. Quote:
Look, if you want to direct chamber load, go for it. It's probably not going to result in rapid breakage--it just stresses parts in ways that they aren't normally stressed and that can cause parts breakage over time. Don't feel like you have to gain a consensus here before you can do it or feel like you need to convince people who know better that it's actually a good idea.
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January 12, 2019, 09:58 AM | #38 | |
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January 12, 2019, 10:02 AM | #39 |
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Here's some "science" for you. Because I'm data-driven (and a big nerd) I once went to the range to test this. I ejected and reloaded (from magazine) the same hollow point round 50 times. I did get a few funny looks and one "do you need someone to show you how to shoot?" offer
But after 50 repeated runs, I fired the round. It fired. Don't know what else to say. Can't say that necessarily establishes anything, but in at least that case, 50 chambering of the round didn't appear to cause any problems. |
January 12, 2019, 10:17 AM | #40 |
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I'm not really surprised. I haven't gone so far as to use my calipers, but in a visual comparison in terms of bullet exposed even after a number of times with both Speer Gold Dots and Federal HST there is little difference. Again in my experience the case body and rim are chewed up before setback becomes noticeable. However, I acknowledge care should always be taken when it comes to setback and that each ammunition type and individual cartridge need to be examined.
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January 12, 2019, 10:21 AM | #41 | |
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With round setback, the pressures generated inside the round can increase, sometimes substantially, and that increased pressure can lead to a damaging explosion that could have damaged both the gun and YOU!! It would have made far more sense to simply measured the round after it had been chambered so many times, but since you didn't understand what the consequences of bullet setback could do, you weren't concerned. If setback is an issue, it can be measured by using a micrometer (or in some cases, a ruler.) Setback rounds need to disposed of safely or disassembled and reloaded. Last edited by Walt Sherrill; January 12, 2019 at 10:35 AM. |
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January 12, 2019, 10:35 AM | #42 | |
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I wouldn't try that with a .40 S&W, it only takes 1/10th of an inch of bullet setback to double the chamber pressure. |
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January 12, 2019, 03:34 PM | #43 | |||
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Anyway, based on that information, IMO, premium self-defense ammo shouldn't set back at all from being chambered a few times. If it does, the ammo maker in question should be contacted.
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January 12, 2019, 05:58 PM | #44 |
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A pistol is not a car or truck. Being a mechanic does not make one an armorer or a gunsmith.
The primers can actually disassemble themselves from repeated chamberings. It has happened to cops who loaded/unloaded the same round over and over over a period of time.
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January 13, 2019, 01:57 PM | #45 | |
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Chambered 50 time?? piffle! I knew a fellow who bought some Federal 185gr JHP .45ACP in 1980. He kept the last magazine full as his home defense ammo. Between 1980 and 2002 when he finally shot them off, those rounds were chambered and rechambered HUNDREDS, if not thousands of times. The nickeled cases had brass stripes on them. All the nickel was worn off the edge of the rim. The bullets NEVER set back on any of those rounds. And, yes, they were measured quite often, to see if it happened. It never did. The gun was a Sig P220. And when fired that ammo performed exactly the same as it had done over 20 years earlier when new. Function was flawless and accuracy was perfect point of aim at 25yds. I mention this, not to imply in any way that today's ammo will do this, or should be expected to do this, but to show that bullet setback is not something that HAS to happen, rather something that usually does happen, these days. And, I say "these days" because, to the best of my recollection, while it has always been a possibility, it wasn't enough of an issue back in the 60s & 70s that much was written about it, then. Clearly something has changed over the years, probably quite a few things.
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January 13, 2019, 04:02 PM | #46 | |
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It may be that ammo is just as well made as ever, but we now have a place to rant, warn, or say what we believe. In the '60 and '70s darned few gun magazines paid that much attention to semi-auto handguns (they had NOT really caught hold back then) -- and there wasn't many other places to share experiences. |
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January 13, 2019, 10:09 PM | #47 |
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Might be the ammo is as well made as it always way, might not be, I can't say, but logic does suggest that if the public is willing to accept ammo that is good enough to stand a few chamberings, then making ammo that will stand unlimited chambering is a waste of money.
Maybe the newer semi auto designs, so popular in large numbers slams the rounds harder than the older designs, perhaps with the intent of increased reliability. We know Glock deliberately uses chambers that aren't fully supported, for increased feed reliability. There's nothing morally wrong with that, nothing says guns intended for military use have to be reloader friendly. Few are, these days. And, ammo that sets back (or has the bullet pulled by recoil) needs to be replaced, which means you buy more ammo, sooner. Good for the ammo companies, I'm sure. If I missed reading a single issue of Guns & Ammo, Shooting Times, and the American Rifleman from the 60s through the 90s, its a very small number. And, I have nearly complete collection of American Rifleman from 1948 through the 90s when I decided to stop accumulating them, because I couldn't afford a bigger house. I think there were a lot of articles about semi auto pistols, its just that in before the wondernine explosion there weren't a dozen makers producing 30 different variants of 3 basic designs, each... Bullet setback? Reloading manual, and articles would all tell you about pushing the nose of the loaded round against the bench (firmly), or something similar, to check for setback, as part of the QC for your handloads. Don't recall much else ever being said about it, even in the Q&A columns. Maybe it existed as a problem back then, but if it did, why not talk about it, we talked about a lot of problems back then, though not nearly like we can today. And that is probably part of it, as well, with our internet instant communication, and nearly unlimited space, it is quite different from a monthly, printed magazine.
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