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mabuse_
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Critical Diameter of AN based explosives
Hi,
i'm new here. My name is Stephan and i'm an electrical engineering student from Germany.
Recently a started enjoying the illegal hobby of playing around with explosives.
Thus far i did HMTD and several H4N2O3 mixtures.
My next victim for further testing will be a not rotten, but dead conifer. The biggest drill bit my Akku-Screwdriver can handle is 18mm, and
fortunately i've got some fitting pipe here.
My favourite is ANNMAL.
Do you think i can detonate that stuff with such a little diameter?
I might also try ANNMSA...
What are your experiences? I don't mean theoretical but in practice. What was the smallest diameter that worked satisfactory?
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Rain
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Hi Stephen.
In my experience your looking in the wrong forum for your answer.
You should definitely have a look at totse.com
They will have the best advice for your idea there.
Look under the "bad idea" section, because thats what this is.
Drowning in my own fear.
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hissingnoise
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If you take the moronic advice of a kewl who can't even get your name right Stephan, you'll get an answer that won't be right and that's worse than no
answer at all.
It's best to forget all about the k3wl collective he touted!
I can't answer your question because I have little interest in AN based compositions but there are others here who will in due course. . .
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Justin
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I reccomend ANNMSA, it should do just fine
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mabuse_
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Hi,
thanks for your answers.
That totse page doesn't look very useful to me, but thanks anyway.
I going to do tests with pipe before i take on that tree and report how it worked, but i'm pinched for time until late june.
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Rain
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I very happy.Pipe bomb vs tree.So interesting!
Drowning in my own fear.
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Justin
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Watch out for supersonic shrapnel when detonating any HE in a metal pipe, and no its not a "pipe bomb" vs a tree, its a AN based HE vs. a tree, just
make sure to take pics or better a video!! Also, Rain, i wouldn't ever use the "B" word again in this forum if i were you. Bombs are intended to kill
or maim people.
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The WiZard is In
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Quote: Originally posted by mabuse_  |
Recently a started enjoying the illegal hobby of playing around with explosives.
My next victim for further testing will be a not rotten, but dead conifer. at worked satisfactory? |
Hudson Maxim - Dynamite Stories. 1916
HOW BENDER LOWERED THE PRICE OF DYNAMITE
ONCE when entering my storage magazine at Maxim, New Jersey,
in which were several carloads of dynamite, along with 37,000
pounds of nitrogelatin, made to fill an order from the Brazilian
Government, I saw John Bender, one of my laboring men, calmly
but emphatically opening a case of dynamite with cold chisel and
hammer. With some epithetitious phraseology, I dismissed him.
It was not long after this incident, when the Boniface of the inn at
Farmingdale, a nearby village, called upon me to buy some
dynamite. He told me that he had employed John Bender to blow
the stumps out of a meadow lot. I related to him my experience with
that reckless person, and tired to impress him with the fact that
Bender was temperamentally so constituted as to court death, no
only for himself but for others about him, when handling dynamite.
But Boniface was unconvinced. He wanted Bender to do the work
and he wanted the dynamite to do it with. Bender, he said, had
assured him that he was a great expert in the handling of
dynamite-that he could so place a charge under a stump that he
could always tell beforehand the direction the stump would take,
and about how far it would go under the impulse of the blast.
Therefore, it was only a question of the price of the dynamite.
"Well," said I, "the dynamite you want is sixteen cents a pound, but
I'll bet you the dynamite against the price of it that John Bender
kills himself with it, so that if he does not succeed in blowing
himself up and killing himself with the dynamite, you can have it for
nothing. On the over hand, if he does blow himself up, you must
pay for the dynamite"
A few day later, there was some hitch in Bender's exceptional luck.
A particularly refractory old stump had resisted a couple of
Bender's dynamic attacks. The failure to dislodge the stump
Bender took as a personal affront, because it reflected upon his
skill as a stump-blaster.
"Next time," said he, "something is going to happen."
He placed about twenty pounds of dynamite under the deep-rooted
veteran, touched if off, and several things happened in very quick
succession. The huge stump let go its hold on earth, and
proceeded to hunt Bender. It was a level race, but the stump won.
Striking Bender on the north quarter, it stove in four ribs, dislocated
a few joints, and damaged his in several other respects and
particulars.
Boniface came to settle for the dynamite.
"Sixteen cents a pound," I said. "Bender hasn't a chance in a
hundred. Wait till the doctors are through with him."
"What do you say to a compromise," suggested Boniface, "of eight
cents a pound? For really," quoth he, "I do not believe that Bender
is more then half dead."
And the account was settled on that basis.
------
Remember —
Don't run after lighting fuse --- use enough that you can walk away.
Don't look up!
Don't worry about the bullet with you name on it. Worry
about shrapnel marked occupant.
The loneliest person in the world is — the one who lights the fuse.
/djh/
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nitro-genes
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Forget the nitromethane! (preferably, the metal piping and blowing down trees as well)
One of the most (cost)effective sensitizers for AN is aluminium powder! At 2-5% aluminium, the critical diameter drops from >10 cm for pure AN, to
<1cm. Yes, were talking mm's here! IIRC, 6mm for a gelled, saturated AN solution with 3% aluminium. Most low temperature explosives, like amine
nitrates benefit from the addition of a few % Al btw, probably by increasing the temperature in the reactionzone...
[Edited on 7-6-2010 by nitro-genes]
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grndpndr
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| Quote: Originally posted by nitro-genes | Forget the nitromethane! (preferably, the metal piping and blowing down trees as well)
One of the most (cost)effective sensitizers for AN is aluminium powder! At 2-5% aluminium, the critical diameter drops from >10 cm for pure AN, to
<1cm. Yes, were talking mm's here! IIRC, 6mm for a gelled, saturated AN solution with 3% aluminium. Most low temperature explosives, like amine
nitrates benefit from the addition of a few % Al btw, probably by increasing the temperature in the reactionzone...
[Edited on 7-6-2010 by nitro-genes] |
Do you by chance have the AN/NM accidentally mixed up?NG?
The NM/ to 5%AL powder,if increased viscositys needed add sublimated silica.FORGET THE AN!,NOT THE NM! if you want a very high det velocity gelled
HE.?!NM/ALNot needed for a tree but great for SC's.
of all kinds as good or better than a cast HE of equivalent vel,
liquid fills every crack crevice has intimate contact with device.
#8commercial or equivalent The patent US 696027 also calls for a small amt of stearic acid,theres enough on AL powder thats already coated with
stearic acid to suffice
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mabuse_
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Hi,
| Quote: |
Forget the nitromethane! |
As far as i know ANNM is faster than AMMONAL.
So the critical diameter should be smaller.
Right?
Considering the pipe, the reason I want to use it is because:
1.) strong confinement lowers the critical diameter
2.) I can compress the AN in the pipe, so there's no disadvantage compared to liquids
3.) I can prepare the charge at home, so it's 100% ready.
I just stick it in the prepared hole I finished before, put the detonator in place and light the fuse. I don't want to mess around to long at the
site, increasing the risk somebody is spotting me.
I might use PVC. The range of it's shrapnels should be lower, but of course it's not as strong as steel...
| Quote: |
Don't run after lighting fuse --- use enough that you can walk away. |
I'm aware of that point. 20-30 seconds of green visco should do.
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nitro-genes
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The topic was named "critical diameter of AN based explosives", not about "high brisance explosives".  Best way to lower the critical diameter of AN is adding aluminium poweder, that was the only point i wnated to make...
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grndpndr
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Forgive the enthusiasm.
You should have enough confinement formed by the hole in the tree w/o any additional dangerous metal pipe.Can you wrap a paper cartridge perhaps even
a coin roll to fit the hole?Maybe a plastic sandwich bag for speed and stealth.
Some handy mud/tapered stick will tamp the hole adding to the limited effectiveness of the 5/95 'ammonal' mix though plenty if confined for a small
conifer, cost effective. If you insist on the pipe device black powder may be all you need and
you wont need a detonator.But long fuse,walk dont run and hope its not a poular place(speed and stealth) as heavy shards of your pipe are likely to
fly about.
[Edited on 8-6-2010 by grndpndr]
[Edited on 8-6-2010 by grndpndr]
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nitro-genes
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"As far as i know ANNM is faster than AMMONAL.
So the critical diameter should be smaller.
Right?"
This is certainly not a general rule, think for example of some safety explosives, like FOX7, TATNB (nuclear bombs), and a more common one, ammonium
picrate, or melt casted TNT. Really insensitive to shock, high critical diameter, though very brisant explosives...
I'm no expert in this matter, though I would think that the energy needed to break the bonds within the explosive on the molecular level
(shock/friction sensitivity) would be far more important. The smaller this "initiation energy barrier" the faster the shockwave will be able to
accelerate, and the smaller the critical diameter. Other factors probably include gas/solids composition and temperature (energy gain) of detonation
etc, determining the length of the reaction zone, and thus how efficient this energy is translated into the shockwave itself....
Ammonal is pretty sensitive stuff for a composition consisting of 98% AN. Just google tannerite...
[Edited on 10-6-2010 by nitro-genes]
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grndpndr
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| Quote: Originally posted by nitro-genes | | The topic was named "critical diameter of AN based explosives", not about "high brisance explosives". Best way to lower the critical diameter of AN is adding aluminium poweder, that was the only point i wnated to make...
|
And its a valid point no disrespect intended(I still need to learn netspeak w/o seeming insulting)
My concern is detonability of an/al in general particularly what was it 2%?I dont have experience with plain an/al.My impression has always been a
boosters required regardless of confinement.The lowest AL/AN ratio ive heard mention of is 10/90 w/booster.I do see 2% approx sulfur used as a
sensitizer
for hard to det AL/ AN mixes.
The confinement you speak MBUSE of will be provided by the hole in the tree and and mud cap or a 1x2 and nails.You dont need a steel pipe for an HE
confinement.The confinement lasts for what a millisecond.If youve seen /used tamping/confinement w/HE you dont need a steel container for it to be
effective OT pipe devices.tamping can range from a sandbag to plywood with long 2/4 studs to act as a brace holding HE to target while providing
adequate strenghth to concentrate majority of hes force against the target.
In fact the steel pipe will reduce the effectiveness of whatever power is achieved w/2%AL/98% AN as alot of the force needed
for the tree will be used fragging the pipe.
[Edited on 13-6-2010 by grndpndr]
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grndpndr
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QOUTE;Nitro-Genes; "Ammonal is pretty sensitive stuff for a comp. of 98% AN.Just google Tannerite..."
FACT CHECK!!!
Tannerite in no way resembles the compositon of ammonal.Off hand Tannerite contains some 65%AN/30% pott
chlorate/titanium sponge and another liquid.There's a patent online and its a common misconception tannerite is AL/AN
or ammonal.Ammonal requires a booster or very large engineer blasting cap and confinement like steel pipe.
Excerpt from Gerald Hurst DEC/06 concerning tannerite;
"Technically a low explosive functions by A diffusion-limited reaction it will explode w/a loud bang in the abscence of confinement."
Ammonal is a HE not a HV explosive but a HE never the less while tannerite isnt a HE and its certainly not AL/AN,Mr Hurst likened it to a Flash
powder.
[Edited on 13-6-2010 by grndpndr]
[Edited on 13-6-2010 by grndpndr]
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Jimbo Jones
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Most of the AN explosives are similar to the so called flash compositions (aka. Oxidizer & Fuel), but the thing is that AN (in big quantities) is
actually prone to detonate even in pure form. Adding some suitable fuel will improve the OB and the AN will be capable to detonate either as fast
burning composition or to achieve full detonation. The list of fuels is endless – Fuel oil, Ethylene & Propylene glycol, Sunflower oil,
Turpentine, Xylene, Toluene, Acetone, Kerosene, Hexamine, Naphthalene, Sugar, Sawdust, Flour, Starch, Aluminum, Magnesium and Zink powders (the last
two are very sensitive to humidity, but reflect both on the cap sensitivity and the brisance). The subject is interesting, but I think is out of the
scope of this forum for sure. Maybe there’s some better and easy to obtain fuels…..who knows.....  .
Now to the questions. Sensitivity and detonation velocity of AN compositions increase with an increase in the charge diameter, the confinement, the
choice of fuel and the temperatures. Both sensitivity and detonation velocity increase with a decrease in the particle size. Sensitivity decrease and
the detonation velocity increase with an increase of the charge density. To put it simple, just use good fuel, fine ground AN and better confinement.
This type of mixtures calls for strong detonator or even booster, but here’s the fun part. The AN & Al combo is really easy to initiated even
with simple homemade detonator and detonate with stable velocity in around 100 gram charges. I have tested mixtures that contain from 3 to 20 %
aluminum powder and the most sensitive ones have aluminum content between 3 and 5 %.
P.S.
Tannerite consists of two components, a catalyst or sensitizers and a bulk material or oxidizer. The oxidizer is a mixture of 85% 200-mesh ammonium
nitrate and 15% ammonium perchlorate, while the catalyst is a mixture of 90% 600-mesh dark flake aluminum powder, 5% 325-mesh Titanium sponge and 5%
200-mesh zirconium hydroxide. Simpler mixtures of ammonium nitrate and aluminum powder are also known to work, but are less sensitive and
harder to reliably detonate.
[Edited on 13-6-2010 by Jimbo Jones]
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the Z man
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In my short experience I have detonated very little charges of AN as I can't experiment in very isolated areas.
I detonated 2g AN/UN 25/75, 2g MEKP/AN 1/9 and 5g AN/EGDN+sand-like Al in 3.5g/0.8g/0.7g ratio. The AN was always activated and pulverized, and the
compositions were all hand pressed in rolled paper tubes with diameters of about 1-1.5 cm for 2g charges and 2 cm for the 5g one.
Always no residue with .1 HMTD .3 MHN in plastic straw.
In the 2g charges the the detonator was even sticked on the side, not stuck inside.
[Edited on 13-6-2010 by the Z man]
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The WiZard is In
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Bad luck often triumphs over physics
EXPLOSION OF A DRILL STEEL SUBJECT TO HIGH TEMPERATURE
Significant Incident Reports No: 19
Subject: EXPLOSION OF A DRILL STEEL SUBJECT TO HIGH TEMPERATURE
INCIDENT
A boilermaker was killed when a drill steel which he was welding to a front end loader
bucket exploded. A length of discarded drill steel (50 mm diameter) was tack welded at
one end to the bucket, and the deceased was heating the steel with an oxy-acetylene
torch to bend the steel to conform to the bucket shape before further arc welding. The
purpose of the drill steel was to act as a wear component, in lieu of hard facing.
There was an explosion and the deceased was struck by shattered pieces of the drill
steel.
CAUSE
The explosion apparently resulted from a build-up of temperature and pressure which
detonated explosive material contained in the hollow core of the drill steel.
A length of drill steel had previously been welded to the other side of the loader bucket
in a similar manner, and the first 150 mm of the core was blocked with tightly packed
material, which subsequent analysis showed to be ammonium nitrate. It is probable that
the length which exploded was cut from the same length of steel as that which was
already welded in place. The amount of explosive material in the core of the rod is a
matter for speculation, but the steel has been disintegrated for a length almost a metre
and it is therefore likely to have contained explosive along much of its length. Only a
very small amount of explosive is required to present a critical hazard in such
circumstances.
COMMENTS AND PREVENTATIVE ACTION
Drill steel (hollow core) which has been in use must be checked before discard or
before it is subjected to any process of cutting, heating or hammering, to ensure that it
has no blockage in the core, as that blockage may consist of, or contain explosive
material.
If blocked drill steel is to be cleaned out for salvage or re-use, then full precautions
must be taken in devising methods to do so. Application of heat, impact, friction or
undue pressure may cause any explosive remnants to detonate. If mechanical means
are resorted to then the process must be done by remote control with total protection of
personnel.
Apart from the hazard potential of explosive remnants in the core, care should be
exercised in the re-use of any discarded percussion drill steel, as it becomes embrittled
in service. It should never be used for holding staging and securing safety lines, nor in
any application where its failure may create a hazard.
Discarded drill steel should never be used to make scaling bars.
http://www.dme.wa.gov.au/mod/publications/sir/explosio.html 23-Apr-97
J M Torlach
STATE MINING ENGINEER February 1991
SAFETY AWARENESS SAVES LIVES
----------
http://www.dme.wa.gov.au/mod/publications/sir/explosio.html 23-Apr-97
This is no longer a valid URL.
I have been unable to find this document at their site http://www.dme.wa.gov.au, however, I do have a hard copy,
from which this was scanned.
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Jimbo Jones
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| Quote: Originally posted by the Z man | In my short experience I have detonated very little charges of AN as I can't experiment in very isolated areas.
I detonated 2g AN/UN 25/75, 2g MEKP/AN 1/9 and 5g AN/EGDN+sand-like Al in 3.5g/0.8g/0.7g ratio. The AN was always activated and pulverized, and the
compositions were all hand pressed in rolled paper tubes with diameters of about 1-1.5 cm for 2g charges and 2 cm for the 5g one.
Always no residue with .1 HMTD .3 MHN in plastic straw.
In the 2g charges the the detonator was even sticked on the side, not stuck inside.
[Edited on 13-6-2010 by the Z man] |
I don’t think the AN/UN mixture is capable to detonate in such a small quantities. Both of the materials are largely insensitive in charges below
100 gr., especially the AN without any active ingredients.
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the Z man
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Yes, I was surprised about the ANUN too. So I carefully looked for unexploded material and I didn't find anything. I think it's unlikely that the cap
entirely pulverized the comp. in the air, also because a failed TNP charge with same design, also hand pressed with the same detonator, left a few big
chunks. Also there was almost no smoke with the ANUN.
I think I'll try again the next week, this time 5g so that if it fails it will be easier to find out.
BTW do you think adding 5-10% sand-like Al will help or it has to be finer?
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nitro-genes
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The shape and size of the aluminium definitely has an influence on the critical diameter, but the size of the AN particles, and density of the mix as
a whole as well. Another surprising influence is water content. Hydro-ammonals tend to have higher densities, lower critical diameters, and tolerate
higher percentages of aluminium without negatively affecting the critical diameter!
Luckily, these kind of factors have been already studied! (attachment)
Surprisingly, even 0.2-0.5 millimeter Al particle sizes can reduce the critical diameter of AN to 25 mm with only 5% added!
Spherical AN below 300 mesh will probably work to get the critical diameter to less than 10 mm! For that matter, even cheap alufoil might work, the
cheapest ones are only 20 um thick, which corresponds to similarly high mesh numbers IIRC.
Attachment: Detonation_properties_of_ammonium_based_explosives.pdf (400kB)
This file has been downloaded 2772 times
[Edited on 14-6-2010 by nitro-genes]
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the Z man
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Thank you nitro-genes for the PDF.
I didn't realize that Al has such a big influence on AN. Now gotta buy a blender to grind aluminium with alcohol (RIP the E&W forum). Using coffee
grinder and salt is messy and uncomfortable...
If I can the next weekend I'll try 5g AN/UN 25/75 plus some Al, to see if one can detonate little quantities of such a mixture and if my coarse Al
takes part in the detonation.If it does will I see the flash or UN will suppress the flame too much?
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The WiZard is In
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This would have been a lot more useful if they had
said what they used as a detonator, and the length
of their tubes.
By da - J L Sherrick, The Influence of Density of Packing
Upon Explosibility of Ammonium Nitrate. Army Ordnance
4 [24] 395-400. May-June, 1924, notes that — "In earlier work [in
this series of reports] the results indicated that TNA
was one of the most efficient boosters for ammonium nitrate."
Strange -
Dobe written down in a book —
Recently, [</= 1983] an about 80-year-old pensioner
[in the FDR] was suspected in spite of his old age,
to occasionally supply against payment anarchist circles with
explosives... During forensic examination of the exhibits the
interest was soon concentrating on a yellow substance similar to
picric acid which had been seized in powdered form, but also
pressed into bars....By IR- and 1 H-HMR spectrometric
methods it was possible to quickly identify this chemical as...
TNA.... &c.
Assuming he is A - still alive and B - out of Gaol maybe he
could be invited to SciMad ....!
[Edited on 15-6-2010 by The WiZard is In]
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mabuse_
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Hi,
I already found that PDF myself, but thank you anyway. The most informative document i could find in the web.
I've got both 100µm Al sand and 4µ Dark Pyro with charcoal phlegmatisation here.
In a popular german homemade explosives tutorial zinc is also mentioned. Unfortunately without any scientific reference.
Does any of you have experience with that?
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