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When the rounds are pushed into case further then when made, are these rounds dangerous. What is the proper disposition of these rounds. I have not had a problem like this before(not noticed anyway) and now I have two jhps that this has happen to.
 

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Probably as the result of loading/unloading? I've seen it, and I have wondered the same. I just take the rounds out of rotation and have not yet decided what to do with them. I won't hurt anything for a little bit of deeper seating, but I don't know at what point it could become unsafe.
 

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If you have a consistent problem with it, get a "Kinetic Puller", that looks like this...
A couple of small raps can move the projectile back out to it's original location, and be safe to shoot...
Firing a cartridge with a projectile pushed further into the case can seriously increase chamber pressure to a dangerous point.
Or as has been recommended, a couple of heavy raps will disassemble the cartridge, into its components, so a reloader can resize the case for more neck tension, and reassemble the cartridge.
 

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They may be dangerous. The volume of the case is reduced by the amount that bullet displaced. If they were near maximum pressure to start with, it is possible that they exceed maximum pressure now.

As was stated above, they can be disassembled and reused, but if you do not reload, it may not be worth it.

I am not sure how to dispose of them.

Here are some suggestions: http://www.wideopenspaces.com/dispose-bad-ammunition-safely/
 

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Probably not dangerous. There have been two studies done on this, one unscientific and one scientific, and both showed setback didn't cause a dangerous overpressure situation.

Be assured that CCI wouldn't release this without having done extensive testing on a number of loads and a number of calibers. This one was released, IMO, because it deals with a high pressure round to start with, so it's more relevant to the discussion of bullet setback.

Edited to add the results of the scientific test:
 

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DO NOT SHOOT BULLETS THAT HAVE SET BACK IN THE CASE!!!!

it only takes one bad bullet to wreck the rest of your life!

very bad advice to pull a bullet with pliers or use a kinetic puller hammer to lengthen a bullet to rechamber and shoot.. boy ooh boy:eek:

that bullet has already lost the neck tension that holds it in proper place. you might get away with it in a break action single shot or a single load only in a revolver. (re read my second line)

rack it or just drop into your semi auto/ pump/lever/bolt barrel, shout the slide and the extractor arm will shove that long bullet into the rifling lands and shove that bullet right back down in the case.

in fact I know longer rechamber rounds that have jammed or dropped on the ground in fear of set back. it just not worth it. I pray my lucky stars in my early years how many times I have done that and got away with it.

having a pretty through knowledge of hand loading I can tell ya that,
depending on the round, (buffalo bore. double tap, jimmybob's handloads) a mire .010 to .020 set back could lead to excessively high pressures and KABOOM!

that's a 1/4 stick with shrapnel wrapped around it in your hand. BE CAREFUL!

p.s. you can take that graph and park it next to your turlet Kermode for the next time taco bell calls...:cool:
 

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to reiterate that graph it doesn't account for powders that do not fill the case to the bottom of the bullet. there are many powders used in bullet construction. fast burning powder for example will have just a smidgin of case fill where as a slower powder with have close to full volume.

I do load .357sig a lot. set back is a real problem with the short bottle neck cartridge. fast powders tend to peak to over pressures quite rapidly and erectly and are generally not used. slower burning larger case fill powders burn at a steady rising curve. they are more forgiving to set back than a fast powder. BUT all powders have funny quirks that just a few tenths of a grain either way can create odd spikes in pressure. bullet seating depth can and does effect burn rate. compressing powder in say a set back will change the burn rate dramatically.

that graph shows just one type of powder. factories use many different types of burn rate powder to achieve the given spec. rate within the same type of cartridge offering. given what they have in stock to use.

so I say flawed data....only takes one bad round:huh:
 

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So, some people believe that the ballisticians and scientists at CCI/Speer are wrong and they are right.

Perhaps, but highly doubtful.

I spent a lot of years working in an industry that had unlimited liability, like the ammo companies CCI/Speer, and I can guarantee you that they published the absolute worst case scenario they found in all their experiments and I can also guarantee they tried each and every powder/bullet/caliber combo they had prior to publishing this.

But, everyone's free to go with their beliefs instead of scientific evidence, that's what makes horse races.

I just don't want to shoot next to anyone who goes with feelings over scientific data.
 

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Flash, I'd love to see similar data with a straight wall case. I believe a necked case, like the 357 SIG, may be a lot more forgiving than something with a straight wall, 40 S&W, for instance. Granted, as the propellant is compressed in the chamber, adverse effects are imparted on the ignition of the powder, hindering efficient and complete combustion. However, if there is no compression of the powder, I would think neck tension would be compromised with the 357 SIG in comparison to a 40 S&W due, in part, to the area of the case wall available for crimp.
 

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So, some people believe that the ballisticians and scientists at CCI/Speer are wrong and they are right.



But, everyone's free to go with their beliefs instead of scientific evidence, that's what makes horse races.

I just don't want to shoot next to anyone who goes with feelings over scientific data.
not looking for a battle of wits, but may I suggest you reread your reloading manuals dealing with over pressures. nowhere in any of mine is "published" that shooting setback rounds is safe.

so if you feel safe using that "scientific data" please shoot your "malfunctioning ammo" in your own private area"
 

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not looking for a battle of wits, but may I suggest you reread your reloading manuals dealing with over pressures. nowhere in any of mine is "published" that shooting setback rounds is safe.

so if you feel safe using that "scientific data" please shoot your "malfunctioning ammo" in your own private area"
Nope, but the graph clearly shows it is safe and my personal experience echoes that.

And by the way, if you look in your owners' manuals for your guns, you'll discover, much to your horror, that shooting reloads is unsafe, but millions of people do it on a daily basis.

Also, nowhere in the reloading manuals does it say that it's unsafe to shoot ammo that has the bullet setback a few thousands of an inch, so the manuals don't say it's safe but they don't say it's unsafe either, so we have an impasse. I suggest you reread your manuals, much as you suggested I do.

Do what you want and I'll do what I want, I was just showing people scientific data. And yes, it is scientific, done in Ammunition laboratories using equipment capable of testing all parameters including pressure under controlled scientific conditions, something almost none of us have at home.
 

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MC:
A little background. I've been reloading since I was 9 and am now retired. I've developed loads for several calibers over the years where there were no published loads and so I'm more comfortable with some things than a lot of people who won't do anything that's not published.

Having said all that, here's a published article by Lucky Gunner, who's pretty well known in gun/reloading circles dealing with setback in a straight walled case.

Like me, he doesn't believe setback causes kabooms, but I'll let you read for yourself.

Battered Bullets: What Impact Does Bullet Setback Have on Function?
Experiment Conducted by: +Andrew Tuohy

I have been conducting experiments relating to firearms for a number of years, some of them quite mundane and others rather unorthodox. Many of the unorthodox experiments have never come to light, either because nothing of value was learned, or because I had decided to compile their results over a long period of time before releasing the data.

One series of tests which falls into the latter category relates to what, exactly, makes guns blow up. We've all seen photos of exploded firearms and bloodied hands or faces that result from a "kaboom," or catastrophic failure of a firearm or the ammunition it fires. As a result, a lot of people exercise an overabundance of caution relating to any ammunition that "looks funny" to them - even going so far as to discard cases with tiny dents in them, for fear of causing an explosion.

While it's always a good idea to err on the side of caution when working with items that contain 1,000 times more pressure than a car tire, it's also a good idea to have an understanding of what can really cause a catastrophic failure. And my experimentation has shown to me that the common knowledge relating to this topic is entirely wrong.

Many others have performed experiments of this type in the past - my interest in the topic was piqued by a conversation with a ballistician who told me of a test performed decades ago by a famous writer. The details of the test made me immediately think, "There's no way the gun didn't blow up!" But not only did the gun not blow up, it exhibited no signs of damage.

Which brings me to the test I conducted using a Glock 22 and some Speer Gold Dot ammunition. I had observed minor bullet setback over a long period of time with this firearm/ammo combination. "Setback" is when the bullet is pushed into the case, sometimes by repeated chambering.

Armed with the common knowledge that .40 S&W was especially susceptible to pressure issues from bullet setback, and that the Glock 22 would blow up if you looked at it wrong, I set out to find exactly what amount of bullet setback would cause a catastrophic failure.

Because I was absolutely certain that the gun would blow up, I took several precautions. First, I clamped the pistol in a vise and fired it remotely using a trigger actuating device. Second, I started with the tiniest levels of bullet setback, using a reloading die to push the projectiles into the case. Third, while firing the Glock, I made sure to put an adequate barrier between myself and the firearm. I then took seven cartridges and set them back at .005" intervals, to a maximum of .035" bullet setback.

I then fired all of these cartridges. Surprisingly, the Glock didn't blow up. Using a dye penetrant designed to identify small cracks, I carefully inspected the barrel and slide. They showed no signs of damage or impending doom.

I scratched my head and tried to figure out why it hadn't turned out the way I expected. I was determined to find out the "zone of danger" for a .40 S&W Speer Gold Dot and a Glock 22 in terms of setback, so I set a few more cartridges back with the press and headed to the range - but not before I grabbed a hammer, too.

As I feared, the further-setback cartridges had no adverse effect, so I slowly looked between the hammer and some of the remaining intact cartridges. I set one cartridge, bullet up, on a smooth hard surface and delivered a solid blow to its face. The result was ugly - the hollow point deformed and the case was bulged a tiny bit, the bullet set back a significant distance.

Due to the bulged case, I had to use the hammer to "ease" the slide into battery. I crossed my fingers and stepped back, then activated the trigger.

No obvious damage.

I took another cartridge and hit it twice, then a third and hit it three times. The end result was disgusting and hardly recognizable - the cartridges were badly deformed and required a solid hit to the rear of the slide in order to chamber. And yet neither caused the firearm to blow up. I hit a few more cartridges with the hammer, but didn't have the heart to fire them - I figured the poor Glock had had enough punishment.

Back at home, I used the dye penetrant and found that the barrel and slide remained undamaged.

Why did this happen?

Well, Glock has revised the barrel since the early "unsupported chambers" which left the pistol with such a bad reputation, and they also beefed up the frame since the earliest iterations of the .40 S&W. And while certain powders, when used in .40, can cause dangerous pressure spikes, manufacturers of commercial ammunition wisely test and select powders that are not as susceptible to changes in temperature or, obviously, bullet setback.

So while I'm not saying that you should attack your ammunition with hammers, I am saying that you should not fear tiny amounts of bullet setback with commercial ammo - at least when it comes to pistol cartridges like the .40 S&W, and especially when you consider that some factory ammo has a natural variation in overall length that does not result in a dangerous condition.

What do you think? Is this something you’d like more details about? If so, let us know. If there is enough interest, we'll publish an in-depth LuckyGunner Labs post detailing more experiments related to chamber pressure.

 

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Thanks Flash for that info.

From what I've read the average 9mm factory ammo is somewhere between 32,000 psi and 35,000 psi. I've also read that +P ammo is somewhere between 36,000 psi and 40,000 psi.

It's hard for me to comprehend that a few thousands of inset will cause the pressure to increase above a +P round (not to even mention the +P+ round).

Also, it's inconceivable for me, to think that reputable manufacturers are producing a product so close to its upper limit that a few thousand additional psi will cause a catastrophic event. Seems to me that in this day and age of litigation that manufacturers would make sure their products can more than handle the +P round. (I think Walther cautions against shooting them but I don't recall others doing so.)

Oh well, I'm just surmising, and found your reference article very interesting.
 

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Thanks Flash for that info.

From what I've read the average 9mm factory ammo is somewhere between 32,000 psi and 35,000 psi. I've also read that +P ammo is somewhere between 36,000 psi and 40,000 psi.

It's hard for me to comprehend that a few thousands of inset will cause the pressure to increase above a +P round (not to even mention the +P+ round).

Also, it's inconceivable for me, to think that reputable manufacturers are producing a product so close to its upper limit that a few thousand additional psi will cause a catastrophic event. Seems to me that in this day and age of litigation that manufacturers would make sure their products can more than handle the +P round. (I think Walther cautions against shooting them but I don't recall others doing so.)

Oh well, I'm just surmising, and found your reference article very interesting.
I'm glad to see what I posted had the desired effect, and that was to get people thinking instead of just accepting what "common knowledge" says about something.

Here's another something for all to chew on. In all the years I've reloaded, I've never had a squib or an overcharge, but I have been standing close to people who have.

Two of these instances were double charges of powder. Let me share what happened:

Instance 1:
A guy was shooting a Sig P220R DA/SA .45 ACP. I heard a BOOM instead of the usual Bang and put my gun down and went over to make sure the guy was okay. He stated the round had some serious recoil and muzzle blast. My examination of the gun showed it was undamaged. He later took it to a gunsmith who also said it was totally undamaged. The load was a double charge of Bullseye powder, 10 grains as he was loading 5 grains normally, with a 230 grain plated bullet on top. A maximum charge of Bullseye for a 230 grain bullet is between 5 and 6 grains according to Alliant, the manufacturer of the powder. So he had a double charge or close to it and there was no damage whatsoever to the gun.

Instance 2: A guy was shooting a Cimarron Firearms .45 Colt. Again, I heard a BOOM instead of a Bang. This one was next to me in the range. At first we found no damage, but further investigation revealed one slightly bulged chamber in the cylinder. The gunsmith found this and no further damage of any kind. The load was a double charge of Hi Skor 700X, 12 Grains. His normal load was 6 grains with a 250 Grain lead bullet. A maximum charge is 6.3 grains, so he was close to double, as was Instance 1. Very little damage considering the double charge.

So, what we're seeing is that it takes a lot to damage a gun, even one that isn't built all that strong like the Cimarron Arms gun.

It should be obvious that a 10% or so increase in pressure isn't really going to do anything to a modern firearm.
 
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