Solution? resetting bullets and that popping noise

[300 RUM]

Well I have 5 pieces of loaded ammo that some one has sent to me for an analysis The ammo was the kind that had the said "popping noise" when resetting a bullet. I won't say there names I'll keep that secret unless they want to disclose themselves. But everyone should give a big hand to that person, I have been asking for the problem ammo to be sent to me for over a year now.

Ok down to business, I just received the ammo so not all testing is complete yet, but I had to start looking for a cause, it is very exciting. I have enclosed some photos not the best but they do show signs of what is going on and I will explain some of it but not all. If you want to know more you will have to pm your number to me and I will call you and chat a bit if you want.

First the brass was in normal condition and the bullet also . The first issues found was some embedded copper jacket into the brass that had torn from the bullet and stuck to the brass cartridge, they ranged in size from 15 micron to 30 micron and obviously freshly torn. The second issued found are a couple of cylindrical rings protruding from the brass and a depression into the softer copper bullet jacket. Other items found were some carbon deposits and some sort of crystallization of a unknown product at this time. Last but not lest the base of the bullet (boat tail to be exact) had oxidation on it, mostly caused by the chemicals found in the powder. Now most powders have additives to prevent oxidation from occurring how ever does not eliminate the possibility. Also double based propellants have NITROGLYCERIN in them, and contain ingredients that range from slight to strong oxidizing properties.

The small particles of copper jacket were removed from the brass and examined for any kind of fusion, the so called "cold fusion", NONE WERE FOUND. The brass and copper were simply latched together with very small protrusions in the brass embedding themselves into the softer copper jacket creating a "Shear effect" when resetting the bullet. It would be correct to say that over time as the brass contracts back to it's original state after sizing a mechanical bond becomes more prevalent.

Currently I have several thoughts on this matter. 1st, unless the bullet and brass are polished to a perfect less then 5 micron surface one may never be able to prevent this occurrence from happening. 2nd the act of polishing the necks with a copper or brass brush after sizing just before bullet seating may reduce the effect but not alive it.

 

[jlow]

Exciting indeed – thanks for sharing your findings. A few questions.

First, did the unnamed donor send you any control ammo i.e. reloading the same manner but more recently to compare?

Second, did you have a chance to do a firsthand seating force determination i.e. with something like the K&M tool to see if they actually seated hard and with that popping noise.

Third , the cylindrical rings protruding from the brass, were those donuts?

 

[300 RUM]

I had five pieces total all loaded at the same time about four years ago. I did do a force test on compressing the bullet back into the case on the other samples. My lab tech reported and avg of 175 pound forces to compression. Yes the ring was all the way around the brass and bullet.

The photo below is the case neck

 

[Tozguy]

Very interesting. Thanks for going to all that work. I'm not sure what to make of the last six words of your post. 'reduce the effect but alive it'.

 

[300 RUM]

Very interesting. Thanks for going to all that work. I'm not sure what to make of the last six words of your post. 'reduce the effect but alive it'.

It may reduce the effect but NOT alive it.

 

[jlow]

Thanks! Don’t have experience with the K&M tool and so can you tell me how the 175 pound force would rate vs. what one would expect for the average seating force?

 

[300 RUM]

Thanks! Don’t have experience with the K&M tool and so can you tell me how the 175 pound force would rate vs. what one would expect for the average seating force?

My test equipment measures the force applied. So as force is applied against an object the pressure goes up and then you look for a break line pressure drop and record that number as pound force. Imagine a digital bathroom scale, place a paper cup on it and then slowly stand on it until the cup folds.

 

[jlow]

Thanks! Don’t have experience with the K&M tool and so can you tell me how the 175 pound force would rate vs. what one would expect for the average seating force?

My test equipment measures the force applied. So as force is applied against an object the pressure goes up and then you look for a break line pressure drop and record that number as pound force. Imagine a digital bathroom scale, place a paper cup on it and then slowly stand on it until the cup folds.

Right, I understand. The question actually is did you see a significant increase in seating force with these specific rounds vs. newely reloaded ones? Without this info, we cannot tell if they are in fact different and so any observation as to why they may be different may be moot?

 

[300 RUM]

Thanks! Don’t have experience with the K&M tool and so can you tell me how the 175 pound force would rate vs. what one would expect for the average seating force?

My test equipment measures the force applied. So as force is applied against an object the pressure goes up and then you look for a break line pressure drop and record that number as pound force. Imagine a digital bathroom scale, place a paper cup on it and then slowly stand on it until the cup folds.

Right, I understand. The question actually is did you see a significant increase in seating force with these specific rounds vs. newely reloaded ones? Without this info, we cannot tell if they are in fact different and so any observation as to why they may be different may be moot?

Gotya, no newly loaded ammo was tested. You are right with out a new case and or freshly loaded control its hard to tell what the actual difference may be.
I would love to have a round that pops at the time of a pressure test just to see the difference in force applied, that would tell a bunch.

I do know one thing , even though I have not experienced this myself with my rounds loaded up to a year in advance, it is good practice to seat long and reseat the week / day/ night before a match !

Now we all have to come up with a correct name for this occurrence?

 

[jlow]

Not a problem, just the ideal situation. Regardless, the 175 pound force does sound pretty high but it would be useful just to know approximately what a regular round of that caliber or even something close would be – do you happen to know?

As for correct name – I vote for “popper” ! ;D Just trying not to be technical so that Wayne won’t get too upset with our scientific endeavor – LOL!

 

[300 RUM]

Not a problem, just the ideal situation. Regardless, the 175 pound force does sound pretty high but it would be useful just to know approximately what a regular round of that caliber or even something close would be – do you happen to know?

As for correct name – I vote for “popper” ! ;D Just trying not to be technical so that Wayne won’t get too upset with our scientific endeavor – LOL!

LOL , I am surprised not more people have chimed in? The pound force is not pound force per square inch just the force applied but actual PSI is about 42.5 psi. a 308 usually takes 250 pound force

 

[BoydAllen]

If you set up a seating die in a press so that the amount that the stuck bullet is pushed back into the case is limited, you should be able to move the bullet, and then measure the force required to move it beyond that point, after it is broken loose. In those instances where you tested the force required to move bullets, was there any sound when they broke loose? If there was not, then you are not looking at examples of what was described as "cold welding". One of the problems with submitting examples of this is that not every round develops the problem at the same time, and the only way to determine if a particular round has, is destructive of the bond. I suggest that if you have any of your samples left that you use a die and press to move a bullet just far enough to break it loose from the initial resistance, and then measure the force needed to move it beyond that point. IMO if you have reached your preliminary conclusions based on samples that are not representative of what is being investigated, your conclusions will not be useful. On the other hand, if there was a popping sound as they broke loose, you are in business.

 

[300 RUM]

If you set up a seating die in a press so that the amount that the stuck bullet is pushed back into the case is limited, you should be able to move the bullet, and then measure the force required to move it beyond that point, after it is broken loose. In those instances where you tested the force required to move bullets, was there any sound when they broke loose? If there was not, then you are not looking at examples of what was described as "cold welding". One of the problems with submitting examples of this is that not every round develops the problem at the same time, and the only way to determine if a particular round has, is destructive of the bond. I suggest that if you have any of your samples left that you use a die and press to move a bullet just far enough to break it loose from the initial resistance, and then measure the force needed to move it beyond that point. IMO if you have reached your preliminary conclusions based on samples that are not representative of what is being investigated, your conclusions will not be useful. On the other hand, if there was a popping sound as they broke loose, you are in business.

The ammo tested/ examined was one that had made the popping nose. The results are stated above. The others used for testing pressure did not render any spikes in the pressure curve.

Further more one can not teach the blind to see colors regardless of what you do. at this point you can continue to call it "cold welding" but you will be wrong, no signs of a Cold fusion bond EVER took place between the brass case and copper bullet.

Boyd now we all need to come up with a correct name for this occurrence anything other then "COLD WELDING"

 

[jlow]

It’s a very interesting experiment as it will help contribute to what we know about this phenomenon, but I would hesitate to conclude that this represent what everyone is seeing when they hear that popping sound and a hard to dislodge bullet.

For one thing, if this round that popped has a seating force of 175 pound force and a regular 308 takes 250 pound force, that does not sound to me like what I am hearing about how hard it is to seat a round when they are “cold welded”.

The other perspective is that this is really an N=1 and there is no guarantee that all reloaders who experience a hard to pull bullet that pops when you reseat it is facing the same physical/chemical interaction seen here.

This does not mean that the study is flawed, just that there is more work to be done. Good job 300 RUM!

 

[300 RUM]

Absolutely , I would think to get a real handle on it, maybe 25 pieces or more would be needed, the problem is you can not predict which one will "POP" and which will not. If everyone would keep sending the ones that POP eventually we would be able to come to a clear conclusion.

I bet it would take 1,000's of rounds of muti year old ammo to conclude an accurate solution

The big find here is that this particular round did not have a cold weld to it, nothing was fused together except for in a mechanical state.

 

[BoydAllen]

The reason that I put "cold welding" between quotation marks was to indicate that while that is the term that is commonly used to describe the topic under discussion, that I was/am not trying to say that actual welding is what is taking place. It would seem that you have wasted your condescension. I don't claim to have actual knowledge of the mechanics of the attachment, just experience with its characteristics, and a successful method for avoiding it. The term cold welding has been used by multiple sources to describe this for decades. I was merely conforming to custom. Some of the posts in these discussions indicate (to me_ that the writer is making conjecture about something that he has never experienced, and therefore has no direct knowledge of. If you heard poppling when moving sample bullets, you have that experience. It is just too bad that the rounds were not in a position so that the force required to make the bullet move as it popped would have been recorded. Perhaps another time.

Also, if you tested after popping, you definitely do not have any data indicating how much force is required to break the bullet free. The reason that I did not send any samples is that many years back, I stopped reloading much ahead of my short term needs. On the other hand if any of you has a spare time machine sitting around, I would be glad to go back say five years or so and put together something to test.

I believe that the suggestion that a larger sample be tested, and that that the force test be applied to rounds that have not had their bullets recently moved is good advice. In my experience, this is not a phenomenon that occurs on a strict timetable, or at a uniform rate within a give batch of ammo. For me, the only real question of interest was how to avoid the problem, once I had figured that out, the only purpose for discussing the topic was to educate new reloaders as to why they might not want to load too far ahead, or clean their necks too thoroughly, a related, but not totally coincident topic.

 

[300 RUM]

The reason that I put "cold welding" between quotation marks was to indicate that while that is the term that is commonly used to describe the topic under discussion, that I was/am not trying to say that actual welding is what is taking place. It would seem that you have wasted your condescension. I don't claim to have actual knowledge of the mechanics of the attachment, just experience with its characteristics, and a successful method for avoiding it. The term cold welding has been used by multiple sources to describe this for decades. I was merely conforming to custom. Some of the posts in these discussions indicate (to me_ that the writer is making conjecture about something that he has never experienced, and therefore has no direct knowledge of. If you heard poppling when moving sample bullets, you have that experience. It is just too bad that the rounds were not in a position so that the force required to make the bullet move as it popped would have been recorded. Perhaps another time.

Also, if you tested after popping, you definitely do not have any data indicating how much force is required to break the bullet free. The reason that I did not send any samples is that many years back, I stopped reloading much ahead of my short term needs. On the other hand if any of you has a spare time machine sitting around, I would be glad to go back say five years or so and put together something to test.

I believe that the suggestion that a larger sample be tested, and that that the force test be applied to rounds that have not had their bullets recently moved is good advice. In my experience, this is not a phenomenon that occurs on a strict timetable, or at a uniform rate within a give batch of ammo. For me, the only real question of interest was how to avoid the problem, once I had figured that out, the only purpose for discussing the topic was to educate new reloaders as to why they might not want to load too far ahead, or clean their necks too thoroughly, a related, but not totally coincident topic.

Several things are very clear after testing even the small amount of given ammo. It does happen! And know we know at least one reason in particular ( PROTRUSIONS FROM THE CASE NECK BITING OR LOCKING INTO THE BULLET)this is obvious seeing one can see the shreds of copper left behind, and there is some kind of corrosion taking place (but not exactly effecting the bullet neck relationship)

Again your right Boyd, It would be really nice to get some ammo that has not been moved and to actually measure the force needed to move the said bullet.

If more people send me there bullets that have been sitting around for years I will continue to test.
There are some remedies that come to mind, but how long will it take to find a true resolve????????????

OH, I do have several other folks that are sending their ammo in , maybe I can find something there as well

 

[BoydAllen]

We will be interested to read your results. As I mentioned in a previous post, a friend mentioned that a common corrosion layer could have formed between neck and bullet, given they are made of copper alloys. Perhaps there might be some merit to this theory?

 

[effendude]

All of these tests and discussions are how we learn, however I wonder if there are so many variables involved in the loading of a single cartridge round that we may never know anything beyond that it happens.... sometimes. We don't load in a controlled lab environment and inadvertantly may add so many variables to the experiement that any findings may be flawed.

New brass or fired brass, how many times fired, how long between firing and reloading the case, level of case neck cleaning, tension, brass, powder, bullet composition and their reaction/interaction, humidity and temp levels during loading and storage, how long between loading and attempting to move the bullet. These are all variables that may have an effect.

As an example, I had an employer years ago whose body chemicals/oils/sweat would literally eat the leather off a new steering wheel in a year. I bet he could make .30 caliber bullets become .284 just by handling them! I read an article on how the AMU loaded ammo years ago. They used rubber gloves when handling primers and bullets as a precaution. They may still do this, I don't know for sure.

My point is we all load, but each one of us introduces so many variables into our ammo that a conclusive finding may never result in any tests.

Scott

 

[300 RUM]

I think the best way to look at it is with the approach that there are so many variables , and if 1 could actually discover a good cause such as a corrosive
Ness or other containment then 1 can simply avoid that particular process use gloves for example