Hello,
Yesterday, I had the idea to recristallize RDX and AP with acetone to get a product which has optimal primary explosive properties. But I failed to make RDX. :rolleyes:

-So, I dissolved one teaspoon pressed AP and two teaspoons of mannitol hexanitrate (very low density) instead of the RDX in some acetone.
-I filtered the solution and dropped the filtrate in 150 ml destilled ice cold water.
-I filtered the precipitated product and dried it in a desiccator.
-Finaly, I pulverised it carefully to a very fine powder (like meal).

When lighted, little amounts of the final product will explode with a loud crack with and -very- little flame can be observed.

It leaves a very little residuum of a waxy brown mass (probably residuums of the MHN :( ).
If little amounts of it are ignited by a hammer, it will detonate violently without residuums.

It seems to be much more powerful and less sensitive than normal AP :) :) :)
And it seems to be a very good primary explosive.



Has anyone ideas or information about the recristallising of explosives other than the above-metioned once together to get an smilar or better product?

Stop apologizing for your 'bad english'. That's a rule violation and highly probable to get you deleted.

OK, sorry! I will edit it now!

A similar secondary/primary mix is mentioned in passing on page 238 of COPAE:

'A mixture of nitromannite and tetracene is a powerful and brisant primary explosive which detonates from moderate heat.'

Mixing with AP could be the easy route when a more powerful primary is required, such as detonating large boosters for stubbon AN comps.

The final product will explode with an loud crack in little ammounts with a -very- little flame if lighted.It leaves a very little residuum of an wax like brown mass (probably residuums of the MHN It will detonate very little ammounts, if it's ignited by a hammer. Than, it leaves no residuum

I think the reason you have the brown residue left when you light it by flame and you don’t have it when you hit it with a hammer is because the MHN is not fully detonating, because it is “somewhat” less sensitive than the AP. which is a good thing if you ask me. This would mean to achieve full detonation this explosive would require a blasting cap. That’s how I see it.

Mixing AP with other explosives dose not sound like too much fun to me. But I am intrigued by you’re studies. Will you be conducting tests on the stability and life expectancy with this explosive?

I'm with Joey on this. Many factors affect the products of decomposition of an explosive: decomp. temp; density of reactant; method of decomposition.
I think it was in Urbanski where I saw two different mechanisms of decomposition for methyl nitrate, one for electrically initiated decomposition, and one for temperature induced (IIRC) decomposition. Different mechanisms tend to yield different products.

So obviously if you radically alter your method of initiation from percussion to heat, you will get different mechanisms of decomposition.

What might have happened is that in explosive decomposition, more energy is released, allowing for the products to be fairly close to elemental (witness nitrogen) or as is what usually occurs, the products are oxides.
But with a lower energy form of initiation, e.g. thermal, the lack of energy does not allow for the products to be so highly reduced. So instead of CO or CO2, what you may get instead is carbon chains for products. One such chain may be responsible for your observed brown residue.

I think the reason you have the brown residue left when you light it by flame and you don’t have it when you hit it with a hammer is because the MHN is not fully detonating, because it is “somewhat” less sensitive than the AP. which is a good thing if you ask me. This would mean to achieve full detonation this explosive would require a blasting cap. That’s how I see it.

I think that when it's used in a pipe (detonator or blastig cap) it will completely detonate, because the AP will initate the MHN automatically due to the pressure and the heat. And if not, I believe that you can initiate it in a tube by a simple flash powder or very little amounts of other primary explosives.

One note: Small amounts of AP will produce huge flames without a crack when it's lighted openly. My product will produce little flames and a crack under the same conditions. :)

I am using that exact mix for years in my caps, as an intermediate layer between AP and MHN, to be able to use even less AP per cap. Very reliable and quite storage stable (6+ month). DONT USE HMTD THOUGH!!!

I have not tried it pure (without AP on top), and I always press pure MHN in as a base charge first. I hate the idea to press something with AP in a vice at 10000 PSI :D

The co-precipitation of the two is new, and probably a good idea. Spares you the separate grinding of the AP, and the diapering later. Did you try different ratios, confined, to see how much AP content is needed for a reliable det?

EDIT:
Just read you last post, it appeared the moment I posted mine.
The cracks are probably from AP crystals (or drops already) getting trapped in the melting MHN. Similar to AP putty which has a much smaller DDT mass than pure AP, with the crystals trapped in the NC matrix.

No, I have never tested different ratios. At the time I have only 10g MHN and about 10g Mannitol at home. So I have not enough MHN to make more of the tests in a bigger scale.
But first I will test this with RDX, CTMTNA and dinitronapthalene instead of the MHN.


Possible improvements:
-Add some ammonium nitrate and ice to the water to get lower temperatures.
-Use more solvent for the explosives than needed.
-Add the soloution of the explosives slowly to the ice cold destilled water.
-Stir like a hurricane.

I have just made some pics and a video of the explosion and the residuums:
http://members.fortunecity.de/potatoguns/recristall.html

It seems to burn much times faster than AP.
It don't makes a huge flame like AP.
(see the Video)

I made a new test.
I mixed 2g AP with 2g CTMTNA and dissolved that in 50ml Acetone.
I filtered the solution. I dumped the filtrate into cold destilled water.
I filtered again. The filtrate is useless. The fine product in the filter is drying now in a desiccator.

The product looks like fine nitrated starch.
It will burn with a huge (not huge than ormal AP) dark-yellow near orange flame and it let some little oily liquid brown residuums, but not 100% dry now and it's definitly much better than normal AP.
It seems to not so good as the MHN/AP co-precipation.

You can see some pics here: http://members.fortunecity.de/potatoguns/recristall.html

There are a few references in the literature which support the idea
of using trimeric AP in mixed compositons .

GB620498 Describes the mixture of 1 part TCAP with 3 parts AN as
being at least as powerful as TNT . However , in the plate tests the
TNT comparable ratio is described as being 1 part TCAP to 2 parts AN .

But what is more interesting is that the TCAP when present in small
percentages in a composition , appears to act as a detonation catalyst ,
which can double the sensitivity to initiation , and increases the brisance
of the composition where the TCAP is present in a small percentage as
5% to 7% to 10% , in combination with TNT . The test results reported
show that a small percentage of TCAP increases the volume obtained in
the Trauzl test by 16% , for compositions where the impact sensitivity
is at the same time increased to an extent that only half the drop height
for the 2 Kg hammer produces detonations for the mixed compositions .

US4196026 Describes the usefulness of organic peroxides as detonation
catalysts , which adds further support to the idea of using TCAP in mixed
compositions . Evidently the contribution of the TCAP is most significant as a
sensitizer and catalyst improving the output of the larger proportion of
other material which constitutes the main charge .

PATR reports compatability of TCAP with PA , TNT , RDX , PETN , tetryl , KClO3 ,
AN , in 40 day tests which showed no decomposition of the mixtures , but
complete volatization of the TCAP from the mixtures . Also PATR reported
that mixtures of TCAP with PA or RDX produced explosives of high power and
high velocity , less sensitive than ordinary primary explosives , but no
details were given other than French patent 893941 and ChemAbstract 47 ,
8374 .

My own experiments have shown that picric acid can be detonated completely
by AP . I secured the complete detonation of 1.5 grams of picric acid by 1.75 grams
of TCAP lightly pressed at a column diameter of 9.5 mm , when a .25 gram
ball of AP putty was used as the " first fire " atop the pressed AP . I believe that
this was close to a threshold condition for successful detonation . Further experiments
are intended to investigate if the sensitivity of crystalline picric acid
can be improved by dampening with a saturated AP solution in toluene and
allowing the solvent to evaporate so that AP is deposited as a residue and
the resulting composition contains 5% - 10% TCAP . Another possibility is to
make a paste of the picric acid with some warm alcohol , to partially dissolve
the PA , then stir together with the toluene / TCAP portion to co-crystallize as
the solvent evaporates . Some percentage of powdered KClO3 or NH4ClO3
added to the slurry could increase the sensitivity of the resulting dried
composition further .

US1533798 Describes that such additions of an oxidizer can improve both
the sensitivity and performance of both base charges and initiators .

These experiments may lead to a formulation and method of preparation for
AP / picric acid based detonator compositions which would be very simple
in terms of OTC attainable materials for compound detonators .

There is another strategy for loading the charge in a compound detonator
which can be used to enhance the effect of the materials being used .
The loading strategy may be useful for improving the performance of
firing trains which are otherwise challenged to work well because of
marginal materials used as initiators . No experiments have been done
by me to observe if this strategy of alternating " layer loading " is of
any benefit . This is a method which may have usefulness or interest
for experimentation .

GB373516 Describes the potential usefulness of " layer loading " the
primary explosive and secondary explosive components in a detonator
for improved performance .

I believe that this is an interesting area for experimentation with TCAP
containing mixtures and firing trains , to reveal what techniques and
mixtures and conditions must be used to secure reliable functioning of
devices employing TCAP as a component . The scope of the possible
usefulness of TCAP in such possible " higher art " applications , even
limited as they may be by storage considerations , has never really
been extensively described , either in this forum or in the existing
technical literature . So there remains a lot yet to be learned and
reported about the potential usefulness of advanced TCAP compositions
and methods .

I would ba careful with all such mixtures. If you use AP to sensitize a base charge, this implies mixing a considerable amount of AP with even more of something, this something being capable of detonating should the AP go off during mixing. Evaporating the solvent would make me especially nervous, I would rather mix in finely blended (with water) AP moistened with a non-solvent.

Though I have used something like this: in all my compound caps I use an intermediate layer of primary+base charge between the two, e.g. 2g MHN, 1/2g of 50/50 MHN/AP, plus 1/2g AP on top. They never failed, while a 1.5g picric acid cap without this intermediate, with 0.75g AP on top in a 1/4" ID cardboard pipe failed completely, only the AP went off.

I would ba careful with all such mixtures. If you use AP to sensitize a base charge, this implies mixing a considerable amount of AP with even more of something, this something being capable of detonating should the AP go off during mixing.No , actually not . I already did a preliminary experiment mixing dry picric acid and dry AP then wetting the mixture with a saturated AP in toluene solution and mixing together the composition which was then dried to a composition containing 27% AP and 73% PA . Loaded incrementally , 2.2 grams of the mixture was topped with 1.5 grams of AP also loaded and pressed in .25 gram portions , then covered with a top charge of .5 grams loose AP . The test charge was fired and the AP/PA base charge failed to detonate completely . From this it was clear that 27% of AP in such a composition was way in excess of the amount which may have a beneficial effect and was functioning as a diluent instead of a catalyst . If 2 grams of AP set off in an enclosed capsule failed to detonate the picric acid deliberately , there wouldn't be much risk
of setting off the mixture accidentally , simply based upon the presence of a catalytic amount of TCAP being present or mixed with the PA . Evaporating the solvent would make me especially nervous, I would rather mix in finely blended (with water) AP moistened with a non-solvent.Water would not provide the cosolvent effect needed for intimate coating and mixing of
the materials . I am sure you are overestimating the danger of such mixtures .
Though I have used something like this: in all my compound caps I use an intermediate layer of primary+base charge between the two, e.g. 2g MHN, 1/2g of 50/50 MHN/AP, plus 1/2g AP on top. They never failed, while a 1.5g picric acid cap without this intermediate, with 0.75g AP on top in a 1/4" ID cardboard pipe failed completely, only the AP went off.Yes that makes perfect sense , given that it is a challenge for picric acid to be detonated
even at a 9.5mm ( 3/8 " ) column diameter by an AP initiator .
That is precisely why some special mixtures and techniques
are required for utilizing PA with an AP initiator in any detonators
of conservative diameter . Without special handling , 1/2 " column diameter is
going to be a more likely working minimum for reliable detonators using AP as
the initiator for PA . The only success which I have had so far at 9.5 mm diameter
was using a ball of AP putty to hot start the compressed AP , and use a lot of it ,
1.75 grams of AP , to be precise . Obviously, there is room for improvement .
PA is a secondary which requires a very solid impulse to intitate , but when it
does high order detonate , it does a very good job . 2.5 grams of PA going
high order will fully detonate urea nitrate . It is good to know what conditions
are needed to secure the reliable detonation of PA by an AP initiator , because
of the OTC availability of the precursors , and the potential high performance
which may be delivered in spite of the low technical complexity of such compositions .
The limitation of what you have to work with can be less significant if you have the knowledge
to make the best use of what you have .