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Old January 5, 2020, 09:59 PM   #26
JohnKSa
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I think this set back stuff is a creature of the net.
No, no it's not.

It's important to keep in mind that we don't live in a world that is 100% defined by the limits of our own personal experiences.

Different ammo, different guns, different practices can all result in different outcomes.

Others have noted setback occurring. Ammunition makers have studied setback. I have seen setback occur in commercial ammunition from as little as a single chambering.

Here is more information on setback including some experiences.

https://www.youtube.com/watch?v=w6PAmKLUcbc
https://www.xdtalk.com/threads/bullet-setback.349873/
https://www.defensivecarry.com/forum...r-too-far.html
https://www.defensivecarry.com/forum...rry-round.html
https://www.luckygunner.com/lounge/w...o-rotate-ammo/
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Take one of these rounds and push down on it as hard as you can.
Pushing on a round is a difficult way to demonstrate setback and unlikely to produce any useful results. It generally takes an impact, (as from the bullet hitting the feedramp during the feeding process) to cause setback, and then often only after repeated impacts.

Here's a slow motion video. At about 7:23 you can see the slide hesitate when the bullet from the cartridge being fed slams against the feedramp. That's obviously a fairly significant impact.
https://www.youtube.com/watch?v=Bp-HFVG_c4Q
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Old January 5, 2020, 10:48 PM   #27
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BS from the net

See my last post. Also look at your handgun as suggested to see the relationship of barrel to feed ramp. No more from me. However, I would suggest you look at the slow motions of the 1925 vintage 45 ACP in slow motion. BS from the net for the most part. That's all folks.
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Old January 6, 2020, 08:50 AM   #28
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It is a problem, and has a marked affect on pressure, and not only with handloaded ammunition. I've had it with factory fresh Hornady .45 ACP rounds, Critical Duty, 220 gr. Flexlock +P, to be specific. Of the 20 rounds, five (5), set back on the 2nd chambering. I caught the first one after it induced a stoppage, then checked the others through the magazine. It was bad enough that I will not buy that type of round from Hornady again. A call to the factory resulted in them wanting the ammunition back, at my expense. Not a good answer.

The gun(s) in question were 1911's: two Rugers and a Sig that exhibited zero problems with other brands of factory rounds, nor with my handloads.

While I can't definitively point to the cause of the problem with the Hornady Critical Duty rounds, I think the nickled case (less friction than brass?) may have less neck tension than a brass one. That, plus the lack of a sufficient taper crimp. For the suspect Hornady Critical rounds mentioned above, I ran them through my RCBS taper crimper and found that they would not setback with 8 chamberings.

NRA used to recommend pushing reloaded ammunition against a solid, non-movable work bench with 40 lbs. of pressure as a means of checking the adequacy of neck tension/crimp depth. I don't know if that is sufficient as the slide velocity/impact has to be reckoned with as well.

Those that deny the pressure implications of set back should spend some time with Quickload, varying the seating depth and see what the pressure curve looks like...it's an eye-opener.

YMMv, but I'll continue to watch my taper crimp depth, and closely examine factory SD rounds that have been chambered multiple times. Rod
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Old January 6, 2020, 10:27 AM   #29
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I say again look at the way your handgun works. Does the nose of the bullet impact on the ramp at ninety degrees. Exactly where is the barrel located when the round is moving out of the magazine? Is the bullet moving up a lowered angled ramp?

Go back and take your gun and slowly feed a round from the magazine into the chamber. Note the angle of the feed ramp to the incoming rounds. Note the movement of the slide as it moves forward with the round. The slide will move forward pushing the round into the chamber as the barrel goes into battery. You will note that the bullet does not go directly against the ramp as the first video states. Hope you have a 1911 for this. You just thought John Browning was smart.

Correct, cartridges must be loaded correctly. Also, seating a bullet deeper will increase presses. Increase to a dangerous level is a variable. I can tell you some about that in a revolver. I can't measure those Hornady bullets with polymer inserts.

Forty Pound Test? The old time reloading advice. Would this be adequate for a round sliding up the feed ramp. In my experience loading 357 SIG and others this forty pounds is adequate. The bullet does not collide with the feed ramp.
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Old January 6, 2020, 12:39 PM   #30
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Ever see a too soft bullet hit the "feed ramp" and simply "dig in" and stop??

I have. And I don't think it matters much if the bullet hits the feed ramp of the barrel or the frame below it, or the top of the chamber when it slides in. Nor does it matter if its actually inertia, with the bullet remaining stationary (briefly) and that "fast moving slide" *(which has traveled, what half an inch? less?) smacking the back of the case and shoving it "up" around the bullet in the reverse of revolver recoil pulling bullets (jumping crimp).

I say it doesn't matter much, because these things whichever is doing it, or all together doing it, these things cannot be changed, without affecting the operation of the pistol.

Bullet "setback" has been a recognized possibility since about the beginning of autoloaders. If you read the literature from pre-WWII on up, until recently, you find that setback was always something mentioned as a possibility, but not ever really discussed, after mention the subject virtually never comes up again. Why might that be? Why is it an issue today, when it really never was before???

Yes, we have dozens of pistol designs and a few calibers that weren't around then, is that the cause? I don't think so. For one thing, we hear about setback in gun designs that were around back then, as well. So I doubt its the guns.

Which only leaves us with the ammo. SOMETHING has changed. If you think nothing has changed, then why is setback such an issue now, when its wasn't for the 100+ YEARS before now???

Look at some old (WWII era for example) GI .45 ammo. There's almost always a case cannelure, right at the base of the bullet. Why? MAYBE the fact that the ammo was used in submachine guns as well as pistols??

Nickel cases doesn't have anything to do with it. I've personally seen Federal, 185gr JHP .45ACP ammo, bought new in 1980, nickel cases, no cannelure, chambered literally thousands of times over a 20year period, with ZERO bullet setback. The nickel cases were worn to the point of having brass stripes on them. ZERO bullet setback. I measured, often. Setback DID NOT HAPPEN.

Now, either there were good faeryes living inside those cases, so that when the bad gremlins shoved the bullet back the good ones pushed it back to where it belonged, OR that ammo was simply made "right".

Which do you think more plausible??

I think ammo is today not being made "the best it can be" but is being made "good enough to work". What is the response we get from ammo makers about setback? Seems they feel its just something that happens, sometimes, and we just have to live with it.

I suspect some bean counter discovered that "if we make this tiny change here, that one there, it won't really affect the ammo, and we'll save $$$$ over the life of the loading machinery."

Don't know if that is what happened, but there has been an effect.

I've seen factory loads that don't setback. MY handloads don't setback. This tells me it is possible to make ammo that does NOT setback.

Therefore, when we get ammo that does, and we're told we have to accept it, because its something that just happens, sometimes, we are being lied to.

Its even possible the lie is not malicious, that the people making the ammo today simply don't realize it is possible to do it in ways that do not suffer setback. After all, the people who made the ammo that didn't are long gone now, pretty much. Also possible it is deliberate, that they do know better, but choose to do it the way they are because its cheaper, and the "occasional" setback "isn't that big a deal".

I can't say its true, and a won't say its not, but there's been talk....
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Old January 6, 2020, 02:25 PM   #31
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As previously stated, it's an issue today thanks to sensationalism. Think about it, literally everything is worse today according to the media at large, even things which have obviously improved are glanced over or otherwise spun in the most negative way possible because unfortunately it's easier to get people's attention that way.

Bullet Setback is effectively a non-issue because once a bullet has been setback far enough to cause pressure spikes high enough to be potentially dangerous, the whole round is so far out of spec that it won't feed from the magazine at all anymore, and by that point it will most likely be easily detectable by the naked eye, ergo anyone with a lick of sense will discard it rather than attempting to chamber it repeatedly until it works then fire it.
In addition, firearms are typically tested with massively overpressure cartridges in order to ensure that they won't explode into shrapnel in the event in which the unexpected may occur or the firearm is subjected to abuse. Proof loads are generally 130% overpressure.
In fact, in most cases in which a catastrophic case failure occurs, the worst that happens is the magazine is forcefully ejected and the grips are damaged. Heck, even in a worst case scenario in which the firearm itself is damaged by an overpressure load, the majority of the damage is due to a chain reaction, and the extent of the damage is usually nothing worse than the slide splitting/peeling rather than exploding into shrapnel because firearms aren't made from brittle metal.

Once more, the dramatic reports of Bullet Setback are highly sensationalized, and based upon outdated circumstantial evidence. It honestly might as well be considered an Urban Legend at this point, because you almost never see substantiated reports of Bullet Setback resulting in a KABOOM, and even when you do it often involves handloads which were most likely loaded irresponsibly or otherwise deliberately beyond the threshold of SAAMI Specifications.

Bottom line, if Bullet Setback alone were truly capable of resulting in a KABOOM, then obviously it would be more prevalent, with endless reports coming in on a regular basis, courtesy of the lowest common denominator who was ignorant of the inherent dangers of repeatedly chambering/clearing firearms on a regular basis.
Furthermore, ammo manufactures would likely have WARNING labels all over every box informing people to be mindful of setback in order to mitigate the risk of lawsuits, and brass cases would most likely be produced with little shelves inside or otherwise taper down to prevent bullets from being pushed back any further into the case.
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Old January 6, 2020, 03:04 PM   #32
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44 AMP: I was working some lead semi-wad cutters through my 1911 after my last post. That bullet would be an RCBS 45-210-KT. I have shot many hundreds of that bullet in that 1911. You must have been dealing with some weird situation to have a bullet dig in. Also, see #31 Post. That RCBS bullet has also worked well in Glock's and my HK UPSC. No problems with good accuracy.

Added: Right on Urban Legend.
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Old January 6, 2020, 03:19 PM   #33
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There have been a couple experiments on the effects of bullet setback:
https://dailycaller.com/2013/03/05/b...etback-matter/
https://www.thehighroad.org/index.ph...riment.238511/
https://www.thehighroad.org/index.ph...art-ii.241596/

Those two individuals conclusion was that while pressure may increase, it probably does not increase enough to cause a kaboom (at least in handgun cartridges).

I wonder if the increase in pressure is less in a cartridge whose bullet is pushed in due to multiple reloadings than it would be if a bullet was seated too deeply and then crimped in place.

On the other hand, removing a cartridge with obvious bullet setback is probably prudent in any case.
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Old January 6, 2020, 07:09 PM   #34
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You must have been dealing with some weird situation to have a bullet dig in.
The weird situation was that the bullet was simply a dead soft slug, too soft to work through the semi auto. A harder alloy hits the feed ramp and slides up.

The point was, in some guns, bullets DO hit the feed ramp.

Quote:
Once more, the dramatic reports of Bullet Setback are highly sensationalized, and based upon outdated circumstantial evidence.
I won't argue with the drama and sensationalism, but when people are posting pictures of rounds with setback TODAY, (meaning something recent, not a pic from decades ago) I don't see how you can say its outdated and circumstantial.

You can't dismiss actual happenings as urban legend, particularly when people are posting pictures of it.

Now the automatic assumption that some setback will turn your gun into a grenade IS flawed. However, you can't dismiss it completely, because its not totally impossible, just very unlikely. As you noted, when a case lets go, the USUAL damage is what you described. But there are rare cases where its worse.

Quote:
It honestly might as well be considered an Urban Legend at this point, because you almost never see substantiated reports of Bullet Setback resulting in a KABOOM,
I think you're overthinking this. If the gun KABOOMS, there's no evidence that there was setback. You can only see setback in a round BEFORE it fires.
Since the bullet, and other things move when the round fires, I don't see where there can be any conclusive evidence of setback left. And, if you don't see setback before the round feeds, how do you even know its there???

If you can't say it was there, and prove it, then it won't be given as the cause of the KABOOM. All you really know is that SOMETHING caused extreme high pressure. And, until you get reports naming setback as the cause or most probably cause, ammo companies aren't going to issue warnings.

Now, if you're doing a test with a known setback round then firing, that's a different matter.

ITs a fact of science that if the pressure in a vessel is X and you reduce the volume of the vessel (and do nothing else) then the pressure per square inch WILL increase.

When you look at the typical tilt barrel locked breech semi auto, what is the weakest point of the "pressure vessel". Remember its not just the case, but the support around it that matters. The weakest point is the case, and its weakest point is where it is unsupported by steel.

Some designs are much less supported than others. What might only be a bulged case in one gun design might be a ruptured case in another, and ruptured cases vent the high pressure gas in the direction of least resistance.

People can say "well setback isn't enough to …." but setback, and its results is an unpredictable occurrence. Most of the time it falls within the observed range, but its always possible for the start to line up and you get results far out of the expected.

Whether or not it is as serious and wide spread an issue as the Internet makes it seem doesn't mean its not happening, because, clearly it is, and people are talking about it. My point is, it shouldn't be happening, and it is. Therefore something isn't being done as well as it could be.
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Old January 6, 2020, 10:02 PM   #35
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Dont work that way.....

The aspect of seating a bullet deeper case will cause an increase in pressure is a given. That's not what's being discussed. Set back is the unseating the bullet and pushing it deeper into the case. In this discussion we are talking about factory rounds or correct reloads. My point is that bullets do not collide with the fed ramp. I have made "dead soft" lead hollow point bullets from a modified Lyman 452378 mold for the 225gr. RN bullet. These dead soft bullets functioned well in a Glock 21 and HK USP Compact. This is not a suggestion to use dead soft bullets in these guns. The makers are very specific about not using lead bullets. The point is that these gun will feed and fire this kind of bullet. That hitting the feed ramp can be dismissed as a cause by actually looking at your handguns as the slide goes forward to pick up a round. Sensationalism? That's running around like a goose with a bell clapper up its tush.:eek
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Old January 6, 2020, 11:40 PM   #36
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Quote:
Originally Posted by 44 AMP
I won't argue with the drama and sensationalism, but when people are posting pictures of rounds with setback TODAY, (meaning something recent, not a pic from decades ago) I don't see how you can say its outdated and circumstantial.

You can't dismiss actual happenings as urban legend, particularly when people are posting pictures of it.

Now the automatic assumption that some setback will turn your gun into a grenade IS flawed. However, you can't dismiss it completely, because its not totally impossible, just very unlikely. As you noted, when a case lets go, the USUAL damage is what you described. But there are rare cases where its worse.
You misunderstand, I'm not arguing that setback itself doesn't exist, (that would be preposterous as well as demonstrably false) I'm arguing that setbacks causing KABOOMs is an Urban Legend with absolutely no concrete evidence whatsoever to back it up.

Quote:
Originally Posted by 44 AMP
I think you're overthinking this. If the gun KABOOMS, there's no evidence that there was setback. You can only see setback in a round BEFORE it fires.
Since the bullet, and other things move when the round fires, I don't see where there can be any conclusive evidence of setback left. And, if you don't see setback before the round feeds, how do you even know its there???

If you can't say it was there, and prove it, then it won't be given as the cause of the KABOOM. All you really know is that SOMETHING caused extreme high pressure. And, until you get reports naming setback as the cause or most probably cause, ammo companies aren't going to issue warnings.
That's precisely what I've been saying! Reports of setback leading to KABOOMs are completely unsubstantiated and based purely on the testimony of those who experienced said KABOOM, and in my experience, they always mention handloads, but never elaborate on the load specifications, which leads me to believe that said loads exceed SAAMI Specifications, ergo the most likely cause of the KABOOM was an overloaded case. Could setback have contributed to the KABOOM? Perhaps, but I'm more inclined to believe that setback is merely a scapegoat used by Bubba to save face rather than assume responsibility for his overzealous handloads compromising the structural integrity of his firearm.

Quote:
Now, if you're doing a test with a known setback round then firing, that's a different matter.

ITs a fact of science that if the pressure in a vessel is X and you reduce the volume of the vessel (and do nothing else) then the pressure per square inch WILL increase.

When you look at the typical tilt barrel locked breech semi auto, what is the weakest point of the "pressure vessel". Remember its not just the case, but the support around it that matters. The weakest point is the case, and its weakest point is where it is unsupported by steel.

Some designs are much less supported than others. What might only be a bulged case in one gun design might be a ruptured case in another, and ruptured cases vent the high pressure gas in the direction of least resistance.

People can say "well setback isn't enough to …." but setback, and its results is an unpredictable occurrence. Most of the time it falls within the observed range, but its always possible for the start to line up and you get results far out of the expected.

Whether or not it is as serious and wide spread an issue as the Internet makes it seem doesn't mean its not happening, because, clearly it is, and people are talking about it. My point is, it shouldn't be happening, and it is. Therefore something isn't being done as well as it could be.
As previously stated, it is possible that setback could contribute to a KABOOM, but it being the leading cause or sole cause is dubious at best. I've read articles on the subject including tests which were performed, (some of which have already been linked to in this very thread) but the results never yielded any conclusive evidence to suggest that there was any truth to it.

In my own personal experience, substantial setback will prevent the round from successfully feeding from the magazine altogether, ergo one would either have to either jimmy it into the chamber somehow or disassemble the gun, drop the cartridge directly into the chamber, then reassemble it and force the extractor hook over the rim so that the slide goes into battery. In either case, I would argue that the shooter is more responsible for any resulting KABOOM than setback itself, as they would have to willingly ignore the fact that the bullet was pushed so far back into the case that it wouldn't even feed anymore, then essentially force the gun to chamber/fire it.

Honestly, make a dummy cartridge at your loading bench right now, then repeatedly chamber it in a pistol with the steepest feed ramp and heaviest recoil spring you've got to quickly induce substantial setback, and tell me how well that bullet feeds. In my experience, it will eventually reach a point in which it just won't chamber naturally, with the case mouth hanging up on the feed ramp, the entrance into the chamber, or the nub of the bullet wedged into the tip of the chamber entrance. Your mileage may vary, but I would be interested in hearing if your results differ from my own experiences.

At the absolute most, bullet setback may be a contributing factor to KABOOMs when coupled with gross negligence, cartridges loaded beyond the pressure thresholds set by SAAMI or recommended in any reputable reloading manual, and/or design flaws present in the firearm such as an unsupported chamber lacking in adequate case head support.
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Old January 7, 2020, 12:02 AM   #37
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Bullet Setback is effectively a non-issue because once a bullet has been setback far enough to cause pressure spikes high enough to be potentially dangerous, the whole round is so far out of spec that it won't feed from the magazine at all anymore,
This is pure nonsense. In some loadings, as little as 0.1" of setback will double the discharge pressure. I have some semi-automatics that will literally feed empty cases, the idea that a round that's a tenth of an inch too short won't feed in a gun like that is not credible.
Quote:
...by that point it will most likely be easily detectable by the naked eye, ergo anyone with a lick of sense will discard it rather than attempting to chamber it repeatedly until it works then fire it.
I agree that it should be detectable, as long as people are aware of the possibility and are keeping an eye out for it. The idea that people would examine every round to see if it's shorter than it was when it was new without understanding setback seems unlikely. But yes, it is detectable by the time it's dangerous.
Quote:
...you almost never see substantiated reports of Bullet Setback resulting in a KABOOM...
1. After the Kaboom, it can be difficult to find evidence of what caused it unless the round was examined before firing.
2. The people who are most likely to experience setback (LE who typically unload and reload/rechamber rounds frequently) have been educated about it as the result of documented incidents.
3. It's not likely to occur to people who shoot nearly exclusively at the range since rounds only get chambered once in most cases.
4. Not all loadings are especially sensitive to setback, so even when significant setback occurs, it's not guaranteed to cause a problem. If it's a lightly loaded round with a light bullet in a cartridge with a decent amount of capacity, then setback isn't going to cause a problem. It's only when the powder space gets very limited that reducing it further by setback can be dangerous.
Quote:
Those two individuals conclusion was that while pressure may increase, it probably does not increase enough to cause a kaboom (at least in handgun cartridges).
Jim Ks first experiment was problematic because he used relatively light bullets for the caliber. Had he tried the same experiment with 147gr bullets, the results could have been much different. Furthermore, he did note pressure signs even though his experiment wasn't designed to maximize the effects of setback by choosing heavy for caliber bullets.

Tuohy's test is interesting, but since he gives us no other information about the cartridges he used for his tests nor the amount of setback in his "hammer tests", it's not really possible to know what the results mean. We know from ammunition manufacturer testing and from pressure calculations that some .40S&W loadings are very sensitive to setback. But the amounts of setback he initially tested were very small--maximum of 0.035"--unlikely to cause problems.

His hammer tests could provide useful results depending on how much the cartridges were setback (which he neglects to tell us) and on what the initial discharge pressures were. If they were lightly loaded cartridges with light for caliber bullets, then even a significant amount of setback would be unlikely to cause a problem, even in .40S&W.

Jim Ks second experiment was closer to what should have been done to really explore the situation. I don't think much needs to be said here because it seems like someone already responded to the important points on that thread.
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...in my experience, they always mention handloads...
As far as I know, the issue first got serious attention in LE and involved commercial ammunition. It may be that more recent attention is focused on handloads, but that's not how it started.
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...it being the leading cause or sole cause is dubious at best.
I'm not aware of any claims that it's the sole cause, the leading cause, or even that it's a common cause of catastrophic incidents. As far as I can tell, while setback is not that uncommon, it's not at all common for all the circumstances to come together in such a way as to result in setback causing an actual catastrophic incident.

It has the potential to cause such an incident, which is why it's important for people to know about it. But I agree, It's not the leading cause or the sole cause, or even a common cause of pistol blowups.
Quote:
At the absolute most, bullet setback may be a contributing factor to KABOOMs when coupled with gross negligence, cartridges loaded beyond the pressure thresholds set by SAAMI or recommended in any reputable reloading manual, and/or design flaws present in the firearm such as an unsupported chamber lacking in adequate case head support.
This takes things too far. It can, in loadings that are sensitive to setback, result in impressively high discharge pressures from properly loaded, good quality, commercial ammunition. Pressures high enough to definitely cause a good quality firearm without defects to explode. Hirtenberger verified this some years ago, and anyone with Quickload can run the numbers for themselves to verify that what their testing showed agrees with the general principles of internal ballistics.
Quote:
Originally Posted by J.G. Terry
No more from me. ... That's all folks.
Quote:
Originally Posted by J.G. Terry
My point is that bullets do not collide with the fed ramp.
I provided a slow motion video of a 1911 feeding showing the slide hesitate when the nose of the round hit the feed ramp. It was quite obvious that the round hit the feed ramp and initially stopped, causing the slide to hesitate/slow before it forced the round up the feed ramp into the chamber.

I think it's pretty clear that the nose of a fed round will hit the feed ramp with significant force at some point in the feeding cycle--at least it's clear to anyone whose ever cleaned a pistol that's been fired with jacketed rounds. The copper streaks left on the feed ramp from the repeated hits from the noses of each fed round are not hard to see and can be difficult to remove.

Another interesting data point is the Beretta PX4. The feed ramp is polymer, but Beretta put a steel insert into the feed ramp to protect it. One wonders what they're protecting it from if there's no impact to it.

Finally, there have been a number of first person accounts on this thread of setback occurring from chambering ammunition. What's the rational explanation for how that happens if it's not that the bullet is being pushed back into the cartridge?
Quote:
That hitting the feed ramp can be dismissed as a cause by actually looking at your handguns as the slide goes forward to pick up a round.
This is a puzzling statement is it's quite plain to anyone who has ever looked at most common autopistols that the nose of the round is aimed at the feed ramp and not directly at the chamber. Furthermore, hand-cycling an autopistol will show that in some designs, the round will impact pretty low on the feedramp where it takes significant force to "bump" it up into the chamber. That force works both ways--if it pushes the bullet forward, the impact also acts backwards against the bullet.

In short, there's a ridiculous amount of evidence that bullet setback does happen under the right circumstances.

There's more than adequate evidence demonstrating that it can result from repeated rechamberings.

There's absolutely no question that reducing COAL while holding other variables constant will increase discharge pressure.

There's more than an adequate amount of evidence that under the right circumstances, relatively minor amounts of setback (e.g. 0.1") can increase discharge pressure sufficient to cause a catastrophic incident. Hirtenberger did some testing that provided those results, but anyone with QuickLoad software can verify them.

Likely? No. But certainly possible. The key is, as Forte S+W points out, by the time it becomes severe enough that it could reasonably be expected to cause problems, it's quite easy to detect. As long as people are aware of the potential problem and haven't been misled to believe it's a total non-issue. That's the main reason to let people know about the issue--because it's so easy to insure you never have a problem as long as you are educated on the topic.
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Old January 7, 2020, 01:03 AM   #38
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JohnKS: You got a surplus of time to be so militantly wrong. Instead of the long rant how about several hours of contemplation on your handgun's feeding cycle. This will keep you from having carpal tunnel syndrome. I have seen the elephants dance and the worlds fair but your tirade (rant)tops all. Spend less time on the net. Briefly put, I stand by what I say on the topic.

Added: Can you define a "personal attack?"
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Old January 7, 2020, 01:08 AM   #39
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I got the idea someplace this thread was closed. Where did that come from?
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Old January 7, 2020, 01:52 AM   #40
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Quote:
I got the idea someplace this thread was closed. Where did that come from?
I don't know. The thread history isn't showing that it was ever closed.
Quote:
Added: Can you define a "personal attack?"
It is common these days for people to fall into the mistake of believing that they are persecuted whenever they are contradicted, to paraphrase Ralph Waldo Emerson, but nothing could be farther from the truth. A personal attack is far different from simple disagreement.

We need to stay on topic (Rechambering Rounds & Bullet Setback) and refrain from trying to change the subject to discussing the people posting on this thread instead of discussing the topic.
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...how about several hours of contemplation on your handgun's feeding cycle...
I'm just geeky enough to have done that already. And with many different types of handguns. Although they do differ in terms of how they operate, it's most common for the bullet to be driven into the feed ramp by the slide during the feeding process. This is why copper marks are left on the feed ramp where the bullet nose hits, it is why Beretta put a steel insert in the polymer feed ramp of the PX4 to prevent damage to the polymer, it is one reason why some types of bullets don't feed well in some guns, it is why the slide hesitates in the slow motion video I posted, and it is why setback occurs.
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Old January 7, 2020, 02:11 AM   #41
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This discussion has raised a few more questions in my mind, so I'll ask them and see what you think.

First, does anyone have any examples of bullet setback NOT from a Browning type tilt barrel gun??

For example from either a fixed barrel semi or one where the barrel just reciprocates in the same plane and does not tilt?
Anyone have any examples of setback happening in a Luger?? or a P.38? Beretta?? or are they all coming from tilt barrel guns?

IF bullets are being pushed back into the case, then they must be hitting something, if its not the feed ramp, what is it??

If bullets are not being pushed back into the case from hitting something and its the slide hitting the back of the case and shoving it up over the bullet (which personally I doubt) then wouldn't the heaviest slides with the strongest springs be the most likely to do that?

So where's the tales of setbacks from Desert Eagle shooters?? Fixed barrel and the heaviest slide and strongest springs you will commonly find. Is it the solid roll crimp of the revolver cartridges that prevents setback there?? What about the .50 AE, its taper crimped. Any reports of setback there? I've not heard of any...

And then there's the "if its set back, its too short to feed" thing. POSSIBLY, IF its enough too short. However some guns will actually feed empty cases, and about all of them will feed rounds shorter than others. The gun can't tell if your round is setback .2" from its spec length or if you're feeding a round with a shorter bullet that is that same .2" shorter when at it's spec length. (and .2" is just a number for illustration)

Seems to be its happening, rarely, but happening only in some duty class semi autos, in certain calibers. We have some proof that the method of chambering and rechambering can affect how often it seems to happen.

My theory is that the ammo is being made just borderline durable enough (and no more) and that sometimes, a round here and there slips over that border and sets back.

Thoughts??
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Old January 7, 2020, 03:01 AM   #42
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Bullet Setback and Your Defensive Handgun

Bullet Setback and Your Defensive Handgun: Check out the video on JohnKSa's previous post. The gun used to illustrate set back is a Glock. Not so, it's an animation that is not accurate. The graphic representation of the fed ramp in relationship to the chamber is not even close. I do have give John credit for consistency in his data and references. Those all are pretty much of the same quality throughout. Thanks to him for his help understanding the problems involved with setback. Incidentally I'm am looking at a G23.4 as we speak. What is the gun that leaves brass stripes up the fed ramp?
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Old January 7, 2020, 03:15 AM   #43
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Comments!

44AMP: To me. it would take some really lousy cartridges to set back the way auto's are made. Who would build an automatic where the nose of the bullet contribute to a malfunction.

I could not get the RCBS SWC dinged up feeding into an unmodified 1911. I'd suggest any skeptics to take their hand guns and slowly let the slide forward feeding a round into the chamber from the magazine. I had used 1911, HK UPSC and G.23 for my little test. John's gun appear to the the Net Blaster Customs weapons.

Comments John? "Everybody knows"...is not an answer. What is brown, stinks and is found in the barn yards?
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Old January 7, 2020, 05:49 AM   #44
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I'm the OP and God Bless you guys I didn't think it would go this far but my original question that ended the post was "should I be worried" is somewhat in limbo.

As I said I have been, as they say, blissfully ignorant, as I have re-chambered rounds countless times, for years, with no problems ....UNTIL the internet made me aware there might be a danger
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Old January 7, 2020, 06:31 AM   #45
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Blown up and gone

JJ45: Obviously you were blown up and are communicating from another world. You would have been fine if you had stayed away from the net.
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Old January 7, 2020, 09:50 AM   #46
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I've experienced bullet setback in my Walther PPK/S, which is a fixed barrel, straight blowback operated pistol. What is causing the bullet to setback? Presumably the steep incline of the feed ramp. It isn't a straight shot from the magazine to the chamber in all fixed barrel firearms.
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Old January 7, 2020, 10:31 AM   #47
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What about the Nambu (-:
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Old January 7, 2020, 12:08 PM   #48
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The easy way to carry one in the chamber without having any chance of this dangerous setback is to drop in a round with the gun pointed at the ground. That is with the slide back & you are in a safe place, then let the slide drop & load the mag.
I never thought about it until everyone started talking about it. I always carry with one in the chamber & haven't noticed any setback on my carry rounds. Then at the range as I was loading up my carry ammo that I realized what I was doing, that I guess others were not. I don't cycle my first round from the mag. I drop it in while the slide is back, then thumb it down to close the slide.
Is this good or bad? It totally stops the chance of causing any setback problems. Is a round cycled from the mag any better than that first round dropped in with the slide back?
This may be something I have to investigate my next trip to the range.
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Old January 7, 2020, 02:04 PM   #49
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Quote:
The easy way to carry one in the chamber without having any chance of this dangerous setback is to drop in a round with the gun pointed at the ground. That is with the slide back & you are in a safe place, then let the slide drop & load the mag.
It's the easy way, but you should NOT DO IT, unless the maker states it is ok.

There are some gun designs where it is allowable, and safe, and some where it is not.
In the Browning 1911 design, and all variants and clones since that have internal extractors, dropping the slide on a chambered round is A BAD IDEA. The gun is designed to feed from the magazine. The rim of the round SLIDES up under the hook of the extractor as it chambers.

Dropping the slide on a chambered round forces the extractor to BEND outward to get over the rim, a place and a direction it was never meant to go. Then it has to "snap" (bend) back in order to hook the case rim. Extractors will USUALLY survive this, for a while, but the can also break from doing this, and/or lose tension, becoming "bent" and no longer properly hooking the case rim.

There are other designs, using pivoting extractors where the gun is designed to allow you to drop the slide on a chambered round without stressing the mechanism. IF the maker approves it, go for it. If they do not, don't do it.

I have one pistol where the owner's manual specifically warns NEVER let the bolt slam forward on a chambered round. I mention this to show that gun designs are DIFFERENT, and what is ok in one could damage another.

Thank you Forte S+W, that is the kind of personal experience I was looking for. Is your PPK/S a .32 or .380?
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Old January 7, 2020, 02:16 PM   #50
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44 AMP: Is there any way you can post a side view picture of your Walther with slide removed and magazine in the gun?
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