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Author: Subject: High-order flash powder?
Hennig Brand
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[*] posted on 1-6-2013 at 06:11


I don't think a person can tell whether an explosive detonated or not by sound. Sound intensity is a logarithmic scale which means every increment on the scale is greater than the last by a factor of 10. The example I heard before (involving car stereos) was that assuming equal efficiencies with speakers, etc, a 100 watt amplifier is only twice as loud as a 10 watt amplifier. Apparently the sound or loudness of an explosion has more to do with the expanding hot gas cloud than anything. Adding aluminum to a detonating explosive actually slows the detonation down, but it can make the explosion so much louder. Our perception of loudness and ability to distinguish sounds is dependent on many things and just isn't good enough to really tell what has happened in an explosion (I think).

Even if you could get flash to detonate it doesn’t compare favorably to the consistency, reliability and good storage and handling properties of most of the true detonating explosives used. Even if it does detonate it is going to be very low order compared to the unequivocal (Rosco term) detonating explosives.

edit:
The best way to tell if an explosive detonated or not is to somehow quantify the damage done by the explosive using a witness plate or something similar for instance. A true detonation has much more destructive power than a deflagration.


[Edited on 1-6-2013 by Hennig Brand]




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[*] posted on 1-6-2013 at 06:47


Quote: Originally posted by killswitch  
Quote: Originally posted by Dornier 335A  
Assuming decomposition into CrO, Na2O, P4O10, CO2 and H2O, one stoichiometric mixture would be 84% Na2Cr2O7, 9% C4H10O4 and 7% P.


Wouldn't some of those sodium and phosphorus oxides be converted to the salt by contact with water vapor from the combustion of erythritol?


Most likely, but that shouldn't affect the oxygen balance.
P4O10 + 6 H2O → 4 H3PO4
The ratios are still the same.
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[*] posted on 9-9-2016 at 16:04


I was wondering if we could restart this this topic, if anyone had through experimentation found any great new ratios or mixtures of flash powder and related compounds?

Yes, I know using 40mg of SADS and 500mg of ETN, PETN or TACP is more efficient and maybe even safer than a few grams of FP for detonating AN mixtures.

So what then is the advantage of using a binary type compound such as FP for detonating ANNMAL, or the Gorden mixture LL posted about recently? It can be done legally without a licence for those of us in the US!! The FP or other binary mixture can be made on site, along with the ANNMAL, and detonated legally just like the exploding targets.

This gentleman needed only .2grams of SADS for detonation, I don't think we are far off from a gram or two of flash powder... we just need to determine the most powerful safest mixture. https://www.youtube.com/watch?v=I3ywcaEOQJQ

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[*] posted on 10-9-2016 at 00:36


Perchlorate/Al detonates if the particle size is small enough and the impact/friction sensitivity relatively low.

I can tell you that a 7.62x39 case full of my KClO4/Al flash will consistantly detonate tannerite and the resulting explosion is much more brisant than tannerite normally is when shot with a rifle.

There are other mixtures besides flash powders which may be of more interest though.

Sodium chlorate, sodium benzoate and a touch of red phosphorus would likely undergo DDT and have a fairly high VoD if properly confined but I'm only speculating, obviously RP/chlorate mixtures can be quite dangerous although with only 5% or less RP I doubt it would be too sensitive.

[Edited on 10-9-2016 by OneEyedPyro]
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[*] posted on 10-9-2016 at 09:01


OneEyed,

Thank you for sharing your experiments. You say my flash powder, what size of Al are you using? I use 2 microns, and when I try to grind it smaller performance is not increased... Dornier's powders obviously do :)

OneEyed, I want to stay away from chlorates, and RP does not seem readily available in reasonable quantities... although the benzoate is an interesting idea.
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[*] posted on 10-9-2016 at 10:58


I just use 2 micron German blackhead and KClO4 70/30. Ball milling it overnight to insure it's as thoroughly mixed as possible definately boosts performance over diapering since the recovered pieces of shell casings are smaller and the report is higher pitched. Of course that doesn't really relate to a binary that can be mixed on site.
-
Chlorate mixtures can be very stable when combined with an appropriate fuel such as petroleum jelly, I'm sure there are other chlorate mixes with reasonable sensitivity that undergo DDT.
I don't think chlorates should be completely overlooked.
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Maybe the addition of a little benzoate could boost the performance of flash powders by giving some gaseous output.
Some experimentation is in order :D
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[*] posted on 10-9-2016 at 12:54


Haha. Funny I was just thinking the same thing... Adding benzoate to flash powder. I would be fine with culottes, if they are stable and a binary ( or even more ingredients) can be made to detonate ANNMAL in small quantities. No way any mix with petroleum jelly is going to DDT.
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[*] posted on 10-9-2016 at 13:01


I should have worded that differently, I know cheddite needs a cap, it was just an example of an insensitive chlorate mixture.
My thought was that there are chlorate mixtures ranging from very insensitive to extremely sensitive so there is likely a mix with decent handling properties that will undergo DDT.
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[*] posted on 10-9-2016 at 14:54


Something else I've been pondering is the use of a mixture containing a fuels and an HE diluted to the point of not being capable of detonation which would exempt it from ATF regulation. A good example of this is how you can buy MEKP in solution as a resin hardener catalyst.

A 40/30/30 mixture of Al/benzoate/ETN would likely be incapable of detonation but might do something interesting in the presence of an oxidizer.

Also what do you mean "culottes"
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[*] posted on 11-9-2016 at 20:39


Quote: Originally posted by OneEyedPyro  
Perchlorate/Al detonates if the particle size is small enough and the impact/friction sensitivity relatively low.

That's interesting, can you demonstrate that it really detonates? A louder sound could be from increased deflagration rates. A bullet impact would ignite the mixture at more than one location, which might greatly increase the burn rate. Years ago I thought explosive mixtures inheritlly deflagrated because there's no set speed of sound through a powder and the reaction proceeds via contact with heat rather than a shockwave. I know I was wrong about that generalization, e.g. potassium/ice or water can detonate on contract despite being very heterogeneous. However this is a coulombic reaction that works because of low surface contact.
In terms of mechanism, what would be the difference between det and def in flash and what's the metric to distinguish it?
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[*] posted on 12-9-2016 at 06:28


Quote: Originally posted by Zyklon-A  

That's interesting, can you demonstrate that it really detonates? A louder sound could be from increased deflagration rates. A bullet impact would ignite the mixture at more than one location, which might greatly increase the burn rate. Years ago I thought explosive mixtures inheritlly deflagrated because there's no set speed of sound through a powder and the reaction proceeds via contact with heat rather than a shockwave. I know I was wrong about that generalization, e.g. potassium/ice or water can detonate on contract despite being very heterogeneous. However this is a coulombic reaction that works because of low surface contact.
In terms of mechanism, what would be the difference between det and def in flash and what's the metric to distinguish it?


Of course powders have a speed of sound.

The only criteria for detonation is that enough energy has to be delivered to the shock wave from the reaction zone just behind the shock wave to sustain it. The shock wave basically crushes the molecules, adding a lot of energy to the system. After it has passed, the products (CO2, H2O, N2, etc.) form and power the wave. The process is basically instantaneous for molecular explosives like RDX with reaction times of around 10-7 seconds. In mixtures, the reaction time is increased because of the diffusion rates. No energy produced more than let's say a cm behind the shock wave will actually power it. So if the particle size of the mixture is small enough, the reaction proceeds quickly enough to add the required amount of energy to the shock wave => sustained detonation.
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[*] posted on 12-9-2016 at 17:13


Quote: Originally posted by OneEyedPyro  
.

Sodium chlorate, sodium benzoate and a touch of red phosphorus would likely undergo DDT and have a fairly high VoD if properly confined but I'm only speculating, obviously RP/chlorate mixtures can be quite dangerous although with only 5% or less RP I doubt it would be too sensitive.[Edited on 10-9-2016 by OneEyedPyro]


Good lord, must every generation rediscover the inadvisability of Sodium chlorate based HE.

5% red P. With Sodium chlorate. And benzoate. How exactly did you lose the other eye, btw? Why not suggest adding some red Arsenic while you are at it.

You will find that surprisingly small ammounts of either red P or Arsenic sulfide added to chlorate mixtures make them FAR more likely to kill you during any dry handling, packing and processing than you seem to expect.

Before the Frasch process and oil refinery byproduct Sulfurs became the major sources, volcanic Sulfur with just a bit of Arsenic sulfide contamination was at LEAST as much to blame for chlorate mixture auto ignition disasters as any sulfurous acids resulting from sublimation/other heat processes used to make roll Sulfur over by the volcano... And you can't so easily wash out that As as you could, perhaps, wash away the acids.

If you must go there, make up a whistle fuel analogue with Potassium chlorate instead of the perchlorate, Sodium benzoate or salicylate, or even gallic acid if you dare, all as you please. Use red Iron oxide or other such catalysts as normal in whistle mixes, while leaving OUT the vaseline or any other phlegmatisers. Compact it hydraulically as for a pyrotechnic whistle. Insert a healthy blasting cap, and don't bother with a metal confinement.




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[*] posted on 12-9-2016 at 19:14


The idea is to create a binary explosive that is suitable for use in caps. Most chlorate based HEs are suicide as a main charge but as a primary to be used in amounts of a few grams or less I think it's a bit more reasonable.

I'm aware of how sensitive chlorate and red phosphorus mixtures are but I didn't know red P is so effective of a catalyst at low concentrations. I assume the mix I mentioned would at least be less sensitive than armstrongs mix but I guess that's not saying much.
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[*] posted on 12-9-2016 at 19:27


Bert thank you for the warnings. I would consider adding Red P to the ammonal mixture for increased sensativity, but NOT the cap.

Bert, using a blasting cap defeats the purpose of my question, something that could be mixed up on site and detonate an AN mixture. Dornier, you are probably the expert on binary ( or more) type flash powders and explosive mixtures. We don't need something increadibly brisiant... If a bullet can detonate ammonal shouldn't a mixture with a burn rate similar to the bullet velocity?
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[*] posted on 14-9-2016 at 02:33


Quote: Originally posted by MineMan  
Bert thank you for the warnings. I would consider adding Red P to the ammonal mixture for increased sensativity, but NOT the cap.

Bert, using a blasting cap defeats the purpose of my question, something that could be mixed up on site and detonate an AN mixture. Dornier, you are probably the expert on binary ( or more) type flash powders and explosive mixtures. We don't need something increadibly brisiant... If a bullet can detonate ammonal shouldn't a mixture with a burn rate similar to the bullet velocity?

Red P and AmmonAl poses no troubles...
It is the chlorate that is troublesome with P...
because P oxydises slowly with air to P2O5 and moisturize from air as HPO3 and H3PO4...
And strong acids with chlorate takes fire or explodes...
-->in the case of a binary (or ternary or whatever) mix of fuel and oxydizer it is as if you have an inflamed match-head inside the mix.
No matter the amount of red P you put into a chlorate mix...it will strongly increase the risk (vs P-less mix) of auto-ignition, self-heating, friction and impact sensitivity... above a certain quantity it becomes 100% chance of explosion.

I have worked with NaClO3/S/C and with KClO3/S/C mixes but I always put 2-5% CaCO3 fine dust to trap the acid traces of the sulfur...so I had no troubles...but such mixes can be deflagrating and in some cases (ultrafine powders and special form of carbon (airborne carbon black of fume)) near-detonating (reducing 5mm wall thickness iron-steel pipe into schrapnels of 5mm on 5 mm and some slighly larger)

I don't know if the CaCO3 methodology could be used to temper the devil inside a red P mix...I would not trust such a mix for storage or > 2g amounts.

The bullet initiation of AmmonAl is based on 3 effects:
1°) The conversion of kinetic energy of the bullet into friction and shock at the impact --> strong heat and compression...especially if the mix contains air bubbles.
2°) The bullet friction with air makes it hot but this is not very efficient
3°) The bullet impact with the container (if metallic) of the AmmonAl generates sparks of ignited iron (burning into Fe2O3)


[Edited on 14-9-2016 by PHILOU Zrealone]




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[*] posted on 14-9-2016 at 02:43


Quote: Originally posted by OneEyedPyro  
The idea is to create a binary explosive that is suitable for use in caps. Most chlorate based HEs are suicide as a main charge but as a primary to be used in amounts of a few grams or less I think it's a bit more reasonable.

I'm aware of how sensitive chlorate and red phosphorus mixtures are but I didn't know red P is so effective of a catalyst at low concentrations. I assume the mix I mentioned would at least be less sensitive than armstrongs mix but I guess that's not saying much.

Chlorate in the sense you use it as a binary mix of fuel and oxydizer will never be a HE...it needs DNT, DNN, TNT, TNN, TeNN to get it as a HE as cheddites explosives.

Chlorate in a conventionnal binary (or ternary or more) mix like Chlorate/Al/S/P will deflagrate and into a cap will be considered more as an ignitor than as a detonator...you may get a shockwave from a deflagration and as such it may maybe initiate sensitive enough secondary like nitrate based ETN, NG, MHN, XPN, IHN, PETN or others like RDX, TNP, HMX, Tetryl...but it will not work wel for less sensitive like TATNB, TNT, TNX.

As explained prior, even traces of red P is like having an inflammed match-heat spot into your mix. It will increase the sensitivity a lot but also the risk of auto-ignition, self-inflamation.

[Edited on 14-9-2016 by PHILOU Zrealone]




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[*] posted on 14-9-2016 at 22:03


I know good quality armstrongs mix truely detonates, has a very small critical diameter and has greater brisance than many HEs. If not for its high sensitivity it would be suitable for use in blasting caps.

Surely there must be another fuse sensitive oxidizer/fuel mixture that is reasonably safe to handle in small quantities but also fairly powerful.

Chlorate/Al flash powder kits are widely available in stores here in the US, it's marketed as an exploding handgun target and hundreds of pounds of it are used daily by people with no concept of what they're dealing with.
Many consider chlorate/Al to be a terribly hazardous mixture yet average citizens manage to produce pounds of it at a time uneventfully.

I understand it's better to be safe than sorry but I also think it's important to be realistic.
I just don't like to see people be overly dismissive because of the percieved or theoretical danger of a substance when in practice it may be relatively safe.

[Edited on 15-9-2016 by OneEyedPyro]
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[*] posted on 15-9-2016 at 04:27


Quote: Originally posted by OneEyedPyro  

I just don't like to see people be overly dismissive because of the percieved or theoretical danger of a substance when in practice it may be relatively safe.


Chlorate mixtures can detonate high order, but they are not a fruitful area for blind research. Your posts are not easy to tell apart from those of an idiot. Much of the safety information in books comes about as a result of deaths. Try reading one.
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[*] posted on 15-9-2016 at 12:43


Only from the home matches is impossible making detonator. However from the Matches and ETN yes. But is it idea for self destruction fools...:cool:...Dr.



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[*] posted on 15-9-2016 at 13:07


I think those targets only have a smaller percentage of chlorite in them. They are not the main oxidizer.

2 grams of KCLO3, Al, and S should work. But I would like something safer... Does anyone have any ideas?
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[*] posted on 15-9-2016 at 13:14


Philou. Did you perform impact and friction tests on your potassium chlorate, sulfur and charcoal mix? How many grams did you use to destroy the 5mm steel pipe? Would you feel safe causally mixing up 2-5 grams of this mixture. Since it can be made in the field it would not need to be stored!

Kind of a different ball game, but my mixture of KCL/NM/Al/NC goes off with a very light wack of a hammer, less than ETN for sure. Chlorates sure are sensitive...especially with NM...


Hmm I just got the idea from writing this last sentence that the above mixture could probably go off with 1 gram of flash, it would be completely legal too. Everything could be made on site:o:P


[Edited on 15-9-2016 by MineMan]
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[*] posted on 15-9-2016 at 14:22


A few decades ago I read an abstract detailing a pyrotechnic mixture with a reliable deflagration-to-detonation transition (DDT). I don't recall the exact composition, other than that it specified a cerium-aluminum alloy (or something to that effect). The downside wat that the time delay was very rough, meaning it wouldn't function with modern delayed ignitors.

So it seems to be possible, although I'm not so convinced pyrotechnic compositions are inherently safer than primary explosives.




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[*] posted on 15-9-2016 at 15:37


Quote: Originally posted by MineMan  
I think those targets only have a smaller percentage of chlorite in them. They are not the main oxidizer.


Believe it or not many of these rimfire sensitive targets are simply KClO3/Al flash powder. Check the MSDS on some of them.
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[*] posted on 15-9-2016 at 16:50


Quote: Originally posted by Fulmen  
I'm not so convinced pyrotechnic compositions are inherently safer than primary explosives.


I strongly agree that they are not... Especially if you are trying for the maximum sensitivity in the expectation that will equate to a higher speed. Different types of sensitivities, different initiation scenarios, different types of outputs. Different does not equal better...

And different amounts are likely to be present at an accidental ignition.

Where you may get by with 10s or a few 100 miligrams of a primary, and limit your synthesis (and handling exposure) to sub gram quantities, some of the devices described here as having been used to initiate AMONAL contain at least several grams of metal fueled compositions- Which are probably being made up in batches of 10s or even 100s of grams. They may not be as FAST as those primary explosives, but they release a LOTof energy, burning metal, Sulfur or sulfide fuels. Thermal dammage and sheer quantity present may more than make up for any difference in brissance related dammages. Burn your body and appendages severely while slightly blowing them off with flash, or utterly shatter them with a highly brissant primary- neither is a good thing.




Boom.
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It was the sort of thing you expected in the Street of alchemists. The neighbors preferred explosions, which were at least identifiable and soon over. They were better than the smells, which crept up on you.
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It is essential that persons having explosive 
substances under their charge should never 
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measures should always be prescribed 
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[*] posted on 15-9-2016 at 17:27


I completely agree, I think some primary's would be safer. But to transport a primary in the states you need a magazine, and placarding, and another magazine to store it on your property, which can not be in a residential area per ATF.

So this is our only option, pyrotechnic mixtures that can be made on site.

Fulmen, can you lead me to that document??
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