I do not Mr Humble is with us any longer.
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I do not Mr Humble is with us any longer.
Well, he did start out here and on another thread like he had a burr in his britches.
Maybe it was something between him and the Gibson fella...?
a m e r i c a n p r a v d a
Be a Patriot . . . expose their lies!
“In a time of deceit, telling the truth is a revolutionary act.” G. Orwell
The "Gibson fella" has no idea who he is and no idea of "something between us"......just tried to help him out is all. Seems he just wanted to argue not only on that thread but several others. Too bad, maybe we could have learned something.......
Larry Gibson
Well, too...his wife coulda been too harsh with him or he just got up on the wrong side of the bed...but, I think he just had a burr in his britches now that we have heard from that 'Gibson fella'....
a m e r i c a n p r a v d a
Be a Patriot . . . expose their lies!
“In a time of deceit, telling the truth is a revolutionary act.” G. Orwell
The best use of this board is to exchange information and have conversations about various cast bullet related subjects. Sometimes folks agree and sometimes they don't. It all works very well, until some guy thinks he has the answer/knowledge and tries to pound others into submission.
It would appear the OP was one such pounder.
Disclaimer: The above is not holy writ. It is just my opinion based on my experience and knowledge. Your mileage may vary.
Didnt he just get unbanned?Originally Posted by starmac
WHEN IN DOUBT, USE MORE CLOUT!
Thank God the situation was dealt with. I really appreciate this forum and if we in a civil way call out to these nutty arguments they will go away. I really appreciate your return Larry and I will always be grateful for all the advise I gleaned from your and others experience!
Look twice, shoot once.
A few days can be quite a while.
I am particularly unconvinced that powders ignite due to conduction within the solid grain. It seems like about as good a conductor of heat as any other celluloid-type plastic, and that is one thing that, unlike the burning rate once ignited, won't vary much with pressure.
I have zero input as to the cause, because I simply don't know, of any type of SEE situation but there appears to me to be ample proof that it has been duplicated in lab tests so I will have to assume that it is a real phenomenon. What I find interesting is that when I first heard of this effect back in the mid 70's the circumstances that were being discussed in the magazine articles of the time was just the opposite of what we think of today, then we were being warned about fast pistol powders in large cases. IIRC it was mostly the popular, at the time, 38 special target loading of 2 1/2 grains of Bullseye with a 158 grain bullet being loaded into 357 magnum cases that was causing all the ruckus. The thought at the time was that this load in the 38 special case was seemingly safe enough but in the longer 357 case it would or could lead to a disastrous detonation, I am assuming this is the same as the SEE events we are talking about today, if not then please excuse my error as I am not in any way trying to disagree with anyone about the cause. I just found this topic interesting and thought I would toss out this other earlier thought on the subject if it is indeed the same thing. Back in those days we of course could only hear one side of the story and had to either take the magazine writer's word for it as being fact or simply disagree without having any practical way of presenting another opinion.
Statistics show that criminals commit fewer crimes after they have been shot
I can't explain SEE, nor have I tried to make it happen, but I do believe it is real, as artillery men have known about it for generations. In small arms, it seems to be limited to smaller charges of slow burning powder in rifles, that leave plenty of airspace.
I also remember the spat of blown up revolvers which were attributed to small charges of fast burning powder detonating. Frankly I discount that, as it occurred about the same time was high volume reloading came into vogue for Cowboy Action Shooting. There was most likely a double charge of powder involved. I also recall that 6/Bullseye was the factory 45 Colt load for several generations.
I really am not a science type and I only offer my observations, recollections and conclusions drawn therefrom.
Disclaimer: The above is not holy writ. It is just my opinion based on my experience and knowledge. Your mileage may vary.
I have no doubt that S.E.E. is a real phenomenon that will occur under certain conditions. Whether or not it is truly an explosion caused but the propellant detonation or deflagrating, or whether it is a case of the bullet being lodged in the bore and then the expanding propellant gasses causing a pressure spike that damages the firearm really doesn't concern me.
Preventing the conditions required for an S.E.E. is all that really concerns me.
I've been about ten inches behind an S.E.E. (6.5 x55 Swede, 156 grains milsurp ammo with a 20% reduced load) Loaded four cartridges for testing - each charge weighed! The first three went without a hitch (albeit rather "weak" sounding), but No. four sounded anything but weak. The bullet never left the gun (lodged in the throat) and the pressure - looking for a way out and only finding to small vent holes - blew back the firing pin with enough speed make it snap in two. The rear part hit me right between the eyes after ricocheting off the knuckle on my thump. It happened almost forty years ago, but I still carry the scars to prove it
S.E.E. is real.
Cap'n Morgan
Unless you count high school in the 1960s I'm not any kind of trained scientist either - not even a failed one. But I agree with what you say. SEE (if you accept the currently fashionably term for something not yet conclusively diagnosed as to cause and train of events), it does appear to be linked to smallish charges of slow powder, and little if at all to fast ones.
The trouble is, it happens extraordinarily rarely. Most firearms failures are due to stupid blunders which the victim, or people doing the shooting while other people became victims or just escaped it, don't want to admit to. "Detonation" or "SEE" are honourable, and perhaps more reliably insurable. False attributions to this effect surely happen, and genuine attributions probably even rarer than they seem. Although there does seem to be a correlation with the use of handloaded ammunition, they are very hard to attribute to any principle factor, even when the rest of similarly loaded ammunition is available for examination.
The scientific method generally looks for repeatable results, firmly tied to one or more variables. (One is best.) We saw, in the other thread, a claim that it can be made to happen one time in six. Very possibly it can. But I think that has limited relevance to something that happens just once in a lifetime, after many more unexceptional shots.
Paul Vieille established the behaviour of a pressure wave only shortly after he invented the conversion of nitrocellulose into a powder suitable for the high powered rifle. He experimented with measurement of pressure at various points along a closed cylindrical vessel in which powder, less than filling it, was confined. If the powder was evenly distributed along its length, and ignited at one end, the buildup of pressure was as progressive as we would expect. But when the powder was concentrated at the ignition end, a pressure wave would build up to a much higher local pressure at the far end. This cushion of very high pressure could even be shown, by a highly sensitive pendulum to measure the location of its mass, to bounce back and forth several times between the two ends of the cylinder.
In some kinds of barrel failure, such as a ring bulge or burst where the projectile is slowed by an obstruction well down the barrel, this wave of pressure is unquestionably the cause. While it may have only a quarter of the bullet's mass, energy equals mass times the square of velocity, and its velocity may be many times the bullet's. But the powder space in artillery is long. I think the main question cast over it as the cause of an obstruction-free smallarms breech explosion, is whether a little more than the length of the case is long enough for it to happen.
Did you mean reduced by 20%, to 80%, or reduced to 20%? I would have thought the former of those would be safe. I suppose between the eyes is good, relative to what might have been. Who would have thought that interposing your thumb in the way of flying metal could do you a lot of good? Assuming you got three reports, three recoils and three bullet-holes as normal, that sounds like this particular effect, all right.I've been about ten inches behind an S.E.E. (6.5 x55 Swede, 156 grains milsurp ammo with a 20% reduced load) Loaded four cartridges for testing - each charge weighed! The first three went without a hitch (albeit rather "weak" sounding), but No. four sounded anything but weak. The bullet never left the gun (lodged in the throat) and the pressure - looking for a way out and only finding to small vent holes - blew back the firing pin with enough speed make it snap in two. The rear part hit me right between the eyes after ricocheting off the knuckle on my thump. It happened almost forty years ago, but I still carry the scars to prove it
S.E.E. is real.
I don't believe the gas-vent holes make the slightest difference to the chances of damage to the rifle. High-speed gas (and it is very high-speed, far faster than a bullet) doesn't change direction easily. The purpose of the vents, and the design of the Mauser bolt shroud which apparently served you well) is to prevent gas heading for your eyes and hands after the tendency to burst the receiver ring has been successfully resisted, and pressure is falling.
"Although there does seem to be a correlation with the use of handloaded ammunition, they are very hard to attribute to any principle factor, even when the rest of similarly loaded ammunition is available for examination"
I would have to disagree to the extent that we now know what the attributable factors that are inherent in or leading up to an actual S.E.E. event. When numerous of those factors are present we can presume (that's all we do after any event has already happened) that an S.E.E. occurred if there is no indication of any other external cause (such as a cleaning rod/tip left in the bore).
There are 9 basic factors to consider when determining if the event was an S.E.E.. The first 2 are measurable only during the event with peizo-transducer or strain gauge pressure measuring equipment. The other 7 can be observed after the event. It is those seven we base our conclusions on as the an event was an S.E.E. event or not. Most often in actual S.E.E. events we will find at least 4 or 5 of those factors readily apparent. Many times, and probably why S.E.E. events are actually rare is that if just 1 or 2 of the factors are not present the event doesn't occur.
An S.E.E. event can come close sometimes though. How many times have we had questions pondered on this forum that during a test string one primer (perhaps more) was extremely flattened showing excessive psi signs while the other primers in the test string did not? I recall just such a recent question asked on this forum. Have you ever had a load that you've used for a long time all of a sudden give a bit of brass flow back into the extractor hole/slot, especially on a cold day?
Anyways the 9 factors of a probable S.E.E. event are;
1. A distinct dip in psi very shortly after the rise in psi begins. It takes approximately 5,000 psi to keep a jacketed bullet moving. The actual amount is variable dependent on bullet fit, jacket hardness, bearing length and bore condition. If the dip in psi is below 5,000 psi the bullet is probably stopped or stopping.
2. A measured increase in peak psi progression as rounds are fired. This progression may be gradual to a point and then exhibit a large jump in psi. The increase may also be very quick with few rounds fired.
Note; the first 2 factors are only measurable with proper test equipment. Since most S.E.E. events occur without the use of test equipment these two factors are not discernible.
3. There is a long throat in which the bullet moves a relatively considerable distance before engaging the leade (rifling).
4. There is an eroded throat that essentially causes a combination of #3 along with a rough surface causing greater resistance to bullet movement.
5. Fouling. This can be from any number of reasons; primer residue, unburned powder, insufficiently burned powder residue, bullet jacket fouling, etc.
6. Case neck tension. Minimal case neck tension on the bullet allowing the force of primer ignition alone to push the bullet out of the neck into the throat.
7. Bullet Hardness and bearing length. Obviously the harder the bullet and/or longer the bearing surface the more psi required to keep the bullet moving. Also a softer bullet that readily upsets may also increase the psi required to keep it moving.
8. Barrel temperature. as more rounds are fired the psi increases. This increase can be especially large if the cartridge is in the chamber for a time prior to be fired. An analogy here would be leaving the round in the hot sunshine prior to firing.
9. Large chamber neck and chamber over case dimensions. Allows more space around the neck and body of the case for gas to expand into before psi is sufficient enough to expand the case and seal the chamber. 5,000 to 7,000 psi are necessary to expand most rifle cases to seal a chamber. The larger the chamber in relation to the case the more psi is required over a longer time. If the bullet is pushed into the throat with 5,000 or less psi by the primer the psi drops as the gas expands into the increased volume before the powder begins to burn efficiently.
Again in our investigations of catastrophic firearm failures we should look first for external an cause for the event such as shooter error (wrong ammunition, continuing to fire after an apparent misfire, leaving a cleaning rod, tip or patch in the bore, not checking the bore prior to shooting for an obstruction, etc.) or reloading error (wrong powder, wrong powder charge as in too much, wrong size bullet, etc.). We look for the external cause first because it is most often the reason for the catastrophic firearm failure. If we can eliminate the probability that an external cause was not the reason then we look for an internal cause; is the firearm itself suspect?
If there is no evidence of an external cause or a firearm defect it is then we look for an S.E.E. event. We look for a combination of probably 4+ of the above factors to be present. If 4+ of those factors (3 through 9) are present we can conclude in all probability the event was an S.E.E.. If we have been measuring the psi with a peizo-transducer or strain gauge and we have factors 1 and 2 present also the proof is rather positive a S.E.E. event occurred.
We can sit around and theorize all we want but at some point a decision can be made, based on scientific readily reproducible factors, as to whether a catastrophic firearm event was an S.E.E. or not. The above are the factors found in a firearms lab while conducting tests of a suspect lot of factory 6.5x55 ammunition. I have found, when measuring psi with an Oehler M43, some of these very factors to occur. I have stopped testing, based on those factors as did the lab technicians, prior to actually creating an S.E.E. event. These events can be "readily" produced. That does not mean they can be produced at will each and every time yet with a little effort an S.E.E. can be produced. I can, without much problem, by just varying test loads produce the 1st 2 factors. No not every time but often enough I pay attention to the psi and time/pressure traces as I test/develop loads.
The German report stated with the .243 Winchester they could produce a catastrophic event 1 in 6 times......that's 3+ times out of a box of 20 shells..........some might not consider that as "readily" but I do.
Larry Gibson
Going through Larry's last post here made me think about the Savage smokeless muzzle loader. I think they stopped production of it now but I wonder if S.E.E. played a role in some of them coming apart? 209 primers and medium fast powders like 5744 and Reloader 7 were recommended.
Oh great, another thread that makes me spend money.
I once heard, or likely prolly read someone explaining their theory about this S.E.E. event. Can't recall the entire explanation or who it was (thought it was someone here), anyway...the part I recall was considering the shoulder angle, the time lag in pressure drop along with the increased volume and then I think he was trying to explain how pressure waves can be additive...as in just the opposite to a standing wave in a transmission line that causes power loss. He was saying that pressure waves can be additive too...as in a rogue wave that occurs at sea.
I'm not knowledgeable in ballistics any further than being smart enough to have not blown myself or my eqpt. up in the last 40 years...but I did get educated about 'standing waves' in transmission lines and believe they are real enough.
Just another observation in this Mystery discussion...
a m e r i c a n p r a v d a
Be a Patriot . . . expose their lies!
“In a time of deceit, telling the truth is a revolutionary act.” G. Orwell
BIS.
The load was reduced by 20% for testing purpose. I came a cross a batch of 500 cartridges at a very reasonable price, and fired quite a few of them without any problems. Then I read in Book of Rifles about several incidents at Danish rifle ranges in the fifties with a distinct lot of ammo. The book had a picture of the cartridge head stamp, and it was the exact same as "my" cartridges! It got me a bit worried, and since the book suggested fouling as the culprit I decided to try reducing the load. I may even have exacerbated the problem by re-seating the bullets without resizing the neck - can't really remember, but I'm positive that it was not an overload mistake as the case was nearly full to begin with, and any "wrong powder" was out of the question.
As for the vent holes, I have noticed the German Mauser 98 has much larger holes (probably by a factor ten) compared to the Swedish Mauser 96.
Cap'n Morgan
That sounds like a classic case of other and unknown factors, besides an 80% load, being responsible.
My friend and I had one each. 6.5X55 swede, long military throats. Mistake was long seating short bullets. Not enough tension to hold bullets. Load was 4831 at the most accurate listed. Bullets popped out and stopped.
As all written that is false, we tried to reduce bullet jump.
I don't think it is the powder choice.
Downloading some powders is wrong but they just fail to ignite and stick a bullet so the next shot is death.
Your SEE is a stopped bullet. If the throat is long enough in a 30-06, stick bullets in 1/8" in the case, eventually you will get an SEE. Just use the neck length to seat bullets.
Weatherby rifles have a long free bore, NEVER seat short.
Not hard to understand at all. You have a bore obstruction before powder lights off.
Done all the time in revolvers like the .44 with strong primers that move boolits before powder burns, the gap saves your butt.
Starting loads of 296/H110 in a .454 with the dumb SR mag can drive bullets into the bore and not light powder. It is a gun that NEEDS a LP mag.
You CAN make it happen with very short bullets seated not deep enough. Long free bore guns the worst.
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