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Flash Powder Safety


mrp0tat0

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Because it is relatively safe, and there is nothing else to replace it with.
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Because it is relatively safe, and there is nothing else to replace it with.

Wally is correct. In addition, stolen fireworks pose much less of a threat if they contain only deflagrating compositions.

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That and if you start putting HE's into 1.3g fireworks, that will change their codes and they will no longer be classified as 1.3g It will cause problems with transportation and making the prices of things go threw the roof.
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The pyro device known as a Gabemort is supposed to contain a large amount of flash powder. IIRC it is a 5lb flash salute hung a few feet off the ground from a stand. also as said above large aerial salute shells can contain large amounts of flash.

 

Yes boomer most secondaries are a lot safer than flash powder due to the possible static electricity ignition although as stated above it would no longer be 1.3g anymore.

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I find it odd that 1 lb of flash has simpler regulations, and less government oversight, than 1lb of TNT or other traditional HE.

 

Purely devil's advocate here - couldn't a 1lb flash aerial salute be replaced with an equivalent HE charge, detonated with a cap or timed primary + boost? The primary and secondary charges can be stored separately, and only come together when the shell is constructed.

 

Again, I am NOT advocating anything of the sort, just trying to learn. I have NO experience with FP. In the hands of an evildoer, would the brissance and destructive power of a true HE exceed that of FP?

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In the hands of an evildoer, would the brissance and destructive power of a true HE exceed that of FP?

I don't mess with HE's, well, technically. I do use flash. As a non-expert, the prop rates of all HE's I'm aware of exceed FP's by at least an order of magnitude. And I believe prop rates are directly related to brissance factors.

 

Which, to someone messing up with a mere few OZ. of flash, is irrelevant. Seems to me I have heard 4 Oz. in close proximity will pretty much shatter a human body to dental record/DNA testing stage.

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I wasn't advocating the use of high explosives in pyrotechnics, just wondering why the traditional pyro associations insist on using compositions that are a thousand times more likely to cause accidents from static, friction etc than many HEs. Is it tradition, or the wish to set their hobby apart from TNT which "the public" (i.e. sensation-hungry reporters) link to terrorists and destruction only, in spite of the fact that by far most of it is used in civil blasting? How many tens of millions of pounds of commercial explosives are used yearly?

 

The thing about converting it into a non 1.3 item is moot here, bulk flash is classified as a HE by the BATFE, and IIRC requires the same storage conditions (type 20 magazine anyone?).

 

With these multi-pound-salutes being limited to professional shows by nature, the argument about stolen items in the wrong hands is moot too, they would have to steal it out of a BATFE-approved magazine in both cases.

 

For the curious, the brisance of many HEs in terms of peak (CJ-) pressure and cutting power (brisance) is 1-2 orders of magnitude higher than the few kilobars of black powder or even flash. You'll never cut structural steel with flash by simply placing it on the steel plates like C-4, but as soon as it comes to blast effects outside of the fireball radius (~1m for a kilo TNT), standard 70/30 flash has 75-80% of the power of TNT.

 

I hope this little essay outside the HE section was allowed, since it gave no recipes but a risk comparison.

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Not uncommon for large aerial or rocket salutes

Really I didnt know that it was "common" to make 5 POUND FLASH BATCHES!!! What types of salutes use 5 pounds point me in the direction so I can see for my self! doest it get to a point where it is just over kill?? as for what to wear while mixin 5 pounds, youd be best off mixin it with NOTHING on!!

Quite frankly, you're are not very experienced in pyrotechnics (really not trying to be insulting at all here), so things like this should be "News" to you... Though, I believe every since Flash powder has been used, it has been used in quantities from a few mg to a 20 pounds...

 

It's quite the tradition in some places to hand a large bag of flash powder at a gallows height and ignite it... I believe this is know as a head bomb... They are awesome :D

 

Also to FrKoNaLeaSh1010, I was told they are called head bombs... They may also be known as Gabemorts.

 

Sorry for using the 'b' word so much here, but a pyro device's name is a pyro device's name.

 

 

Quite frankly I believe Flash powder has no brisance, since it propagates through the air, and not a shockwave (deflagration vs. detonation), though I know the sheer force from a close-proximity explosion will shatter your bones, burst your organs, etc...

 

Brisance is defined as the rate of speed a detonation reaches its peak pressure. Therefore, no detonation, no brisance... Flash powder still creates a high enough pressure to shatter the body though.

 

 

Here's a nice example of a big salute rocket.

Cplmac's 3" whistle to 1.5 lb. flash?

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[

Quite frankly I believe Flash powder has no brisance, since it propagates through the air, and not a shockwave (deflagration vs. detonation), though I know the sheer force from a close-proximity explosion will shatter your bones, burst your organs, etc...

 

Brisance is defined as the rate of speed a detonation reaches its peak pressure. Therefore, no detonation, no brisance... Flash powder still creates a high enough pressure to shatter the body though.

Hmmm Well, it IS known that one flash device will "ignite" another in close proximity. IS this not a coliorary of the definition of detonation?

 

I am ignorant of most HE information, as I said, it has no use <yet> in my applications. I AM curious, however. No bad knowledge yanno...

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Yes one flash device set next to another will set it of but I always thought that had more to do with the fact that the first device will shatter the casing of the second and the flash/fireball will ignite it. It doesn't detonate so i highly doubt its a shockwave setting off the second one.
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The change in pressure may cause another flash device to ignite... It could also be from one device breaking another device open, and then igniting it by the flame propagation. Of course the heat created from one ignition is probably the true cause of the second.
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It doesn't detonate so i highly doubt its a shockwave setting off the second one.

My mentor in the field demonstrated to me the hazards and some of the characteristics of flash. He bored 6 1" holes in the ground about 2" deep and 6" apart. Into each went about 30G flash. Covered them with dirt, and fused the first. Trench.

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HE's in fireworks is the stupidist idea I have heard, flash safe, there is no need for HE's.

 

If they started selling shells loaded with PETN and AN mixes, not only will the cost skyrocket so will the storage and shooting requirements. You could have a whole show dissapear if one shell failed to clear a gun. Not to mention that every little display company will be forced to close. If you want commercial HE's they are impossible to get without serious connections, put them in fireworks and you could have a real problem.

 

Anyway, its not going to ever happen. China will never allow it, shipping will be impossible and chances are the HE will shatter every star in the shell.

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I highly doubt they were talking about using a high explosive to break a shell as the logic behind that is obviously flawed. I am sure they were talking about using it for reports and nothing more if anything. I still dont really see need for any HE in pyro except for maybe nitrocellulose.

 

Also technically flash powder is an HE according to the ATF so i dont think that would change the storage or shipping as anything that contains flash powder "technically" contains a high explosive according to the government.

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The Chinese almost exclusively use KP and BP coated rice hulls in their shells, or granulated KP, so they don't have to pay HE shipping, but bulk firework freight is still expensive as all get out.

 

I can't believe people actually considered that HE's would be used as a break\salute charge... Are you serious? You must not be very experienced in Primaries if you are thinking about setting them next to a Secondary and launching that out of an HPDE mortar while on the same Acre of land.

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Shipping, storage, etc tend to hinder this, but the licensing really comes into play. Say you have a license to manufacture high explosives from the government. If you actually manufacture high explosives, or try to buy them, you are still going to jail for a long long time. Unless you have a legitimate use, you are fucked licensed or not. Fireworks is not a legitimate use.

 

Other than that, I would feel quite unsafe with the primary in there. The shock from the lift is a bit unsettling. Now, I am sure there is some combination that could work, but this is not the place to discuss it. Additionally most clubs have specific regulations against high explosives, you'd have to be on your own land, and could never compete with them. You'd never get a permit if they were in a show. So at the very best they'd be for your own personal enjoyment. In very big salutes, it's rare to see "good" blackhead/perc composition. They exist, but offer no real advantage over some of the cheaper and much less reactive compositions. There is a system of diminishing return, so no one in their right mind uses the expensive stuff when cheap materials will do the same job.

 

FYI any stupid posts here will result in immediate 2 week vacation. Don't care who you are, you're gone, no exceptions.

 

 

 

 

Also, flash powder can detonate. Just does not do so under normal conditions.

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I feel I need to reiterate that I am NOT advocating HE in fireworks, I'm simply trying to understand, to learn. The basic, theoretical question was simply "If flash is the devil, but HE is safe to handle, and the goal is a report/salute, then why did FP become the comp of choice for this?"

 

I thought the answer might be "FP is easier to make than a true HE" but it appears that the correct answer is that the sensitivity of the primary in a shell with an HE report makes it untenable... THAT I can understand. It makes some sense. But an artillery shell has an HE charge and the necessary fuze (w/primary) to survive a lauch of 100's of "G's", vastly more than a fireworks mortar tube.

 

Again, I am hoping this is just an intellectual discussion of the physics of the process.

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I don't understand. This thread was supposed to speak about the safety of handling flash powder, but you turned it in a discussion of using HE's in fireworks.

:blink:

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Yes, this discussion has veered way off-topic. Let's keep this on-topic please: Flash Safety.

 

Safe and cautious is the order of the day when dealing with it. Minimize your risks using the information in this thread, but realize you will never eliminate the risks. A healthy respect for it will keep you in one piece,

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I am sorry. I have a tendency to promote thread drift. And please 50AE, for the THIRD time I am not saying "Yeah, let's use HE in fireworks." I simply enjoy discussing theoretical concepts. If we were to discuss atomic weapons in a forum, that doesn't mean that the goal is to construct or use one.

 

I do understand the sensitivity of the topic, and I will desist.

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  • 4 months later...
I'm reporting a small incident of a friend, who wanted to make a little KMnO4 flash powder to test its sensitivity. The composition was 6 KMnO4 : 2 Aluminium : 2 Sulfur. His flash powder IGNITED spontaneously during the diaper method. Luckily, it was a small batch and he received a little 1st degree burns. Just to warn you if you consider using KMnO4.
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I'm reporting a small incident of a friend, who wanted to make a little KMnO4 flash powder to test its sensitivity. The composition was 6 KMnO4 : 2 Aluminium : 2 Sulfur. His flash powder IGNITED spontaneously during the diaper method. Luckily, it was a small batch and he received a little 1st degree burns. Just to warn you if you consider using KMnO4.

 

Hmm isn't the KMnO4 not supposed to contact organic material? Like a paper sheet for diapering?

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50AE, I hope your friend realizes how lucky he is to have escaped with only a minor burn.

 

And to anyone reading this thread for the first time, Potassium Permanganate has ZERO uses in Pyrotechnics, let ALONE in Flash. Spontaneous ignition is a real possibility, as 50AE's friend now knows.

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Don't worry, he will remember it for life :D

 

Though I think potassium permanganate can be useful to ignite thermite with glycerine.

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Don't worry, he will remember it for life :D

 

Though I think potassium permanganate can be useful to ignite thermite with glycerine.

 

Hmm trying to think when the last time I seen a good thermite shell... ;{)

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