Sciencemadness Discussion Board

Detonation of Double Based Smokeless Propellants/Powder

holmes1880 - 10-2-2011 at 23:20

We know that DBSP detonates. I've tested it, and seen videos. As little as 300 mg PETN base charge will detonate 70% of DBSP brands.

A Bullseye brand, one of the fastest burn times, has 40% NG and 50-60% NC. However, it has fairly low density. I assess it within 5000 m/s VOD, but the density, I think makes its RE factor only around 0.8....like TATP. Agree, disagree?

Discuss, gentlemen.

[Edited on 11-2-2011 by holmes1880]

DougTheMapper - 11-2-2011 at 08:07

The problem here is that DBSP comes in the form of grains. Just having grains in general obviously entrains quite a bit of air and significantly reduces density, even with a bit of ramming.

Ideally, one would find a solvent for the fastest DBSP available and cast it into monolithic blocks for maximum density and thus VOD. Perhaps make it into a gel with acetone, cast it into a mold, and then vibrate the crap out of it to get rid of air bubbles. This would definitely up the RE factor per volume and the resulting block would probably closely resemble that of a fixed-shape polymer-bonded explosive.

Be that as it may, http://www.docstoc.com/docs/26842885/VoD-of-Various-Energeti... says that the NC in DBSP has a VOD of around 4500m/s but fully nitrated NC can push 7300m/s. Combined with NG's 7700m/s, the monolithic casting may end up somewhere around 6000m/s if you get lucky. Maybe not enough for a shaped charge, but possibly an EFP and certainly an inexpensive and insensitive booster.

I've often thought about the use of loose DBSP in binary compositions as an inexpensive sensitizing agent. Has anyone tried AN/DBSP?

[Edited on 11-2-2011 by DougTheMapper]

quicksilver - 11-2-2011 at 09:11

Due to the polymer in most all DBSP acetone would bring the material into a heavy or thin solution capable to re-hardening. At that juncture the particulate would settle into a solid. (allow bubbles to become eliminated though settling obviously).
determining the % of many DBSP is sometimes a challenge. Most think that Bullseye has the highest with (approx 40%) but Hogden also has a 37% (Titegroup), etc, etc. The level of NG doesn't necessarily determine the absolute level of energy however. The level of accessibility does. The higher the level of polymer & other inerts in ratio to that of the energetic has some influence in the way it molds to a SC. That's one of the reasons why a great deal of research was done on the design of plastiques, which can sustain a level of up to 30% inerts and shoot viably. There is a difference between NG and RDX in the way it sustains it's response to inerts in a solid mass.

Polyester is not SBR or polybutene adjusted to a given solid energetic. The relationship of polyester to NG is not the same as SBR or polybutene to RDX or PETN. There are factors outside of a simple "mold and shoot". To differing energetics and two differing interts give very different results.

Rosco Bodine - 11-2-2011 at 09:43

RE is TNT equivalency, given within reason charge density being equal,
RE is simply a weight for weight output comparison. The nature of the
target material of course matters also when practical equivalency is the
thing being estimated for "work done" by an explosive shattering a target.
Bulk strength is a different parameter entirely. If you were to fill a 1 liter
container with granulated TNT and compare the blast effect to a 1 liter
identical container of granulated DBSP having the same charge density,
then the weight for weight TNT equivalency of the DBSP would be likely
125% or more. Comparing apples with apples would be comparing granular
TNT with DBSP at equal charge density. Block TNT would have a more bulk strength which would skew the test, which would then be comparing apples and oranges and would tend to make the TNT appear more powerful when weight for
weight is is actually much less powerful than either guncotton or nitroglycerine.
A better apples to apples comparison would be to compare blasting gelatine with block TNT ....both solids.....and then the "equivalency" issue would be settled
by testing on the basis of weight for weight, with each material at "optimum"
or normally used charge density ....whatever that turns out to be.

grndpndr - 11-2-2011 at 11:41

Ive seen many questions involving plasticizing DBSP or a single base IMR NC owderv and incorporating various energetics.

IIRC I even wondered about the efficacy of incorporating Mekp/DBSP while still plastic from the acetone.What the consistency of the result would be I dont have a clue it was just a mental excercise.Others have suggested ETN,MHN etc etc.As has been suggested the stabilizers added to any SP would help with stabilizing the composite.I would think an added bonus would be its water resistant- proof nature.Given some flexibility
in a wax paper covered block or cartridge form with double sided tape attached a crude plastique might be achieved with limited flexibility depending on composition, a high VOD?Again dependent on composition.With the ability to be attached to whatever substances a double sided tape adheres to?Armor,concrete,stone,debarked tree trunks,Mailboxes?Thats a potential fed charge as well however! (And sure fire attention getter) Your aware of how well that behavior/megalomania served
Gotti!?Despite his forebears advice /experience.

PS as to ridding the plastic material of voids I wonder if vigorous
vibration similar to the way a concrete vibrator rids concrete of 'popcorn' voids.Just so happens I saved a set of vibrators from a lazyboy type chair that really rock and roll.Original thought was the vibratory action bolted to the same plywood as a
hotplate would provide some stirring activity.Not so much! as it turned out!

Rosco Bodine - 11-2-2011 at 12:28

It is an incorrect assumption and incorrect generalization that the stabilizer most commonly used for smokeless powder is also effective in stabilizing other nitroesters either alone or being used in a blended composition. A different less basic stabilizer may be required for a blended composition using ETN or other nitroesters. Stabilizer compatability schemes are very carefully worked out and there is no "universal stabilizer" found in diphenylamine in particular. For MHN for example dicyandiamide is reportedly very effective as a stabilizer. MEKP does not seem like a good prospect for mixing with DBSP because MEKP is somewhat unstable and more reactive, compared to AP.

grndpndr - 11-2-2011 at 13:53

Quote: Originally posted by Rosco Bodine  
It is an incorrect assumption and incorrect generalization that the stabilizer most commonly used for smokeless powder is also effective in stabilizing other nitroesters either alone or being used in a blended composition. A different less basic stabilizer may be required for a blended composition using ETN or other nitroesters. Stabilizer compatability schemes are very carefully worked out and there is no "universal stabilizer" found in diphenylamine in particular. For MHN for example dicyandiamide is reportedly very effective as a stabilizer. MEKP does not seem like a good prospect for mixing with DBSP because MEKP is somewhat unstable and more reactive, compared to AP.


Id be reluctant to argue the point as I was simply repeating IIRC anothers post concerning the stabilizers in the commercial product aiding in stabilizing a composition.Of course it would depend on the specific addition to be able to determine if Diphenlamine was useful.Regarding acidity which could well be a lingering problem with ETN. As well as lingering Acidity in commercial NC/NG DBSP doesnt seem to be unheard of or the use of diphenlamine in single base NC propellants or DBSP due directly to acidity and degradation of the product over time would be abandoned.You arent suggesting the stabilizer diphenlamine is detrimental to the ETN/DBSP composite are you?Detrimental to DBSP/MHN?Or just not Ideal for the purpose?

Assuming the lab made ETN/MHN was as clean of acidic impurity as the commerciial DBSP counterpart what likely problems do you forsee?Can you reccomend other energetic sensitizers that would be more suitable for our purposes given thier limited scope,limited availability of stabilizers? Im not concerned with storing the DBSP-NC/ ETN-MHN other energetic sensitizer for the 60plus years that surplus ammunition propellant has been proven to be stable for.
Most likely 6days,6wks,6months stability is more than enough at least for me.And should the composite become degraded some definite signs would be noticed.Smell,fumes etc.

Will you kindly explain your last sentence in which you state..
"..MEKP is somewhat unstable and more reactive compared to AP." This seems contrary to every other post Ive seen on this /other forums as well as scientific testing with friction ,impact etc as indicators?All due respect Roscoe,Ive read many of your posts often considering it a last word on the subject but this has me confused.Not an abnormal state of affairs But.. W/in the scope of this discussion I dont see any glaring errors in my post?

Rosco Bodine - 11-2-2011 at 14:54

Quote: Originally posted by grndpndr  
Quote: Originally posted by Rosco Bodine  
It is an incorrect assumption and incorrect generalization that the stabilizer most commonly used for smokeless powder is also effective in stabilizing other nitroesters either alone or being used in a blended composition. A different less basic stabilizer may be required for a blended composition using ETN or other nitroesters. Stabilizer compatability schemes are very carefully worked out and there is no "universal stabilizer" found in diphenylamine in particular. For MHN for example dicyandiamide is reportedly very effective as a stabilizer. MEKP does not seem like a good prospect for mixing with DBSP because MEKP is somewhat unstable and more reactive, compared to AP.


Id be reluctant to argue the point as I was simply repeating IIRC anothers post concerning the stabilizers in the commercial product aiding in stabilizing a composition.

What people assume may be logical does not necessarily prove to be true when tested by experiment. A common mistake I see in discussions thought to be "scientific" is people lecturing about things they don't really know, but fail to use any qualifying language that would reveal they don't really know for certain what they are "teaching" by descrbing as a fact....particularly when it really isn't a fact what they are saying at all.
Quote:

Of course it would depend on the specific addition to be able to determine if Diphenlamine was useful.Regarding acidity which could well be a lingering problem with ETN. As well as lingering Acidity in commercial NC/NG DBSP doesnt seem to be unheard of or the use of diphenlamine in single base NC propellants or DBSP due directly to acidity and degradation of the product over time would be abandoned.You arent suggesting the stabilizer diphenlamine is detrimental to the ETN/DBSP composite are you?

Right, I am not "suggesting" such a proposition at all, I am declaring it to be the case, at least so far as a couple of experiments done with melts of ETN and DBSP composites, the stability is poor for such mixtures in combination, while the stability for the uncombined separate components is excellent.
Quote:

Detrimental to DBSP/MHN?Or just not Ideal for the purpose?
I have done no experiments on DBSP/MHN composites so I am not certain, but I would expect the pH sensitivity of MHN to be similar to ETN, so I would expect a more nearly neutral pH stabilizer would be indicated as more useful there as well as for ETN.
Quote:

Assuming the lab made ETN/MHN was as clean of acidic impurity as the commerciial DBSP counterpart what likely problems do you forsee?
The problem foreseeable with any contemplated stabilizer is that it may actually react with the thing intended to be stabilized by its reactivity desired to be limited to neutralization of decomposition byproducts. A prerequisite is that the stabilizer be unreactive towards the thing desired to be stabilized, and only react with the byproducts.
Quote:

Can you reccomend other energetic sensitizers that would be more suitable for our purposes given thier limited scope,limited availability of stabilizers?

It is unclear to me what is desired to be accomplished,
what is wished to be sensitized for what purpose.
Quote:

Im not concerned with storing the DBSP-NC/ ETN-MHN other energetic sensitizer for the 60plus years that surplus ammunition propellant has been proven to be stable for.
Most likely 6days,6wks,6months stability is more than enough at least for me.And should the composite become degraded some definite signs would be noticed.Smell,fumes etc.

I am still not really understanding what composite for what purpose you are asking about.
Quote:

Will you kindly explain your last sentence in which you state..
"..MEKP is somewhat unstable and more reactive compared to AP." This seems contrary to every other post Ive seen on this /other forums as well as scientific testing with friction ,impact etc as indicators?All due respect Roscoe,Ive read many of your posts often considering it a last word on the subject but this has me confused.Not an abnormal state of affairs But.. W/in the scope of this discussion I dont see any glaring errors in my post?

It wasn't meant to be cryptic, and it was true what I said.
MEKP is more chemically reactive and thermally unstable than is AP (TCAP)....so even though you may get away with
making AP putty from acetone DBSP and AP ....that doesn't mean that MEKP will also work just because it is also a ketone peroxide. Plasticising DBSP with MEKP isn't likely
to increase its sensitivity either .....so it isn't really clear
what is trying to be accomplished.

grndpndr - 11-2-2011 at 19:09

Im often quilty of repeating what I had presumed to be fact once its been repeated enough,many others are as well.At some point believing unsubstantiated assertions to be true.Im not denying thats a failure but there s more to this thread than misinformation.
There are also practical goals,whether there attainable or not Im not qualified to give a certain answer on way or another.
In my posts I qualified all my statements and I have simply posed some questions
based on previous experience w/MEKP-nitrates.An assumption but the idea of a composition of DBSP and MEKP,ETN or MHN is certainly not unique to me and my interest is based on the results from the combination of MEKP/AN-other nitrates power and sensitivity.

The idea was of course to add to the power and sensitivity of DBSP whether using mekp or ETN etc. Along with increasing DBSPs density by plasticizing the grains and molding into blocks or cartridges in all likely hood increasing DBSP's density and VOD.

"Mekp is more chemically reactive and thermally unstable than AP" But in fact AP is also
more sensitive to shock and friction than Mekp. I sense your making an assumtion, "plasticizing
DBSP with Mekp isnt likely to increase its sensitivity either" so you are in fact making an assumption based on? for which you roundly criticize others.

"so it isnt really clear what is trying to be accomplished." It would have been had the thread been read.The Ideas may or may not be practicable but its perfectly clear whats trying to be accomplished.Increased sensitivity/VOD from a DBSP-NC/ % nitroesters.Thats the Goal Rosco,if experimentation or FACT comes to light in regards
the goal and it proves the concept to be impractical fine,no harm no foul.

[Edited on 12-2-2011 by grndpndr]

Rosco Bodine - 12-2-2011 at 01:02

Quote: Originally posted by grndpndr  
Im often quilty of repeating what I had presumed to be fact once its been repeated enough,many others are as well.At some point believing unsubstantiated assertions to be true.Im not denying thats a failure but there s more to this thread than misinformation. There are also practical goals,whether there attainable or not Im not qualified to give a certain answer on way or another. In my posts I qualified all my statements and I have simply posed some questions
based on previous experience w/MEKP-nitrates.An assumption but the idea of a composition of DBSP and MEKP,ETN or MHN is certainly not unique to me and my interest is based on the results from the combination of MEKP/AN-other nitrates power and sensitivity.

You may think you are connecting the dots logically where you really aren't doing that. MEKP and inorganic nitrates
is a fuel oxidizer system that is very different from an MEKP and nitroester system. Nitrates are way more stable and less reactive than nitroesters. Some chemical mixtures are okay and other chemical mixtures are not okay with regards to stability issues. Some explosives complement stability when they are mixed and certain others will adversely affect stability in mixture. Just because you think you can physically mix different materials doesn't make the idea a good one in practice if the chemistry and physical properties are not a good match.
Quote:

The idea was of course to add to the power and sensitivity of DBSP whether using mekp or ETN etc. Along with increasing DBSPs density by plasticizing the grains and molding into blocks or cartridges in all likely hood increasing DBSP's density and VOD.
There is no plausible theory to apply to the scenario of MEKP mixed with DBSP in hopes of adding to the power of DBSP. There is a plausible theory how using a liquid nitroester like NG would do that, and what you would have is blasting gelatine. MEKP is not a substitute for NG. Want blocks? well press the DBSP into a block. Moistened with a bit of acetone it will fuse nicely under pressure. But you will get something like a plastic brick which will be hard to detonate. So blasting gelatine is really the way to go there. DBSP is what it is and MEKP is not likely to magically transform it into blasting gelatine.
Quote:

"Mekp is more chemically reactive and thermally unstable than AP" But in fact AP is also
more sensitive to shock and friction than Mekp. I sense your making an assumtion, "plasticizing
DBSP with Mekp isnt likely to increase its sensitivity either" so you are in fact making an assumption based on? for which you roundly criticize others.
An educated guess as basis for a qualified statement is not an unfounded assumption at all. I qualified the statement saying "isn't likely". The basis for the statement is that MEKP is a lower energy material than DBSP which would function as a diluent, and the applicable generality is that diluent included plastiques are going to be harder to detonate than either of the components, so it is a reasonable and qualified statement that I made, not really an assumption stated for fact. I will stand by that qualified statement as probable fact.
Quote:

"so it isnt really clear what is trying to be accomplished." It would have been had the thread been read.The Ideas may or may not be practicable but its perfectly clear whats trying to be accomplished.

I did read the thread and it still isn't clear what is the purpose or the logic involving the materials being discussed.
If the purpose is to densify and sensitize DBSP then use
NG and make blasting gelatine which is stable and proven,
and incorporates a mixture of materials that makes sense.
Quote:

Increased sensitivity/VOD from a DBSP-NC/ % nitroesters.Thats the Goal Rosco,if experimentation or FACT comes to light in regards
the goal and it proves the concept to be impractical fine,no harm no foul.
[Edited on 12-2-2011 by grndpndr]

There is no reason indicated to hope that MEKP is chemically
or energetically inclined to act in a way that complements
DBSP .....it doesn't make sense from a chemical or physical standpoint. Blasting gelatine is a known quantity.
The OP was asking and musing about the RE of DBSP as being .8 or so and comparable to TCAP and that is just wrong and way low. That's a FACT. MEKP would be probably .4 RE and that wouldn't lift up DBSP that is RE 1.25 or better .....
it would only drag it down.
So the math there simply doesn't work, even before getting to the stability issue.




[Edited on 12-2-2011 by Rosco Bodine]

pjig - 12-2-2011 at 11:30

@ Rosco
What is your take on the old "nipolite " HE that was used as grenade?

It is like what you described above, dbsp wet and mixed with a petn or other HE, then pressed into a mold. The initiator can be threaded into the hardened grenade. (No need for a shell" the explosive is the shell)...

I think that a earlier thread went into some depth on making SC's with a composite matrix of these energetics. Not sure if the petn would be the best choice, but it seems much more stabilized than etn, or any other peroxide exp.

I think that dbsp bullseye is claimed to have a vod of 19,000fps- 25,000fps range on its own. I read it in a study done on detonating smokeless powders.

* How much harder do you think detonating a "dried"block of wet and compressed dbsp will be in relation to the powder form... ( will it need a booster, or would a composite cap be enough)?

[Edited on 12-2-2011 by pjig]

grndpndr - 13-2-2011 at 11:21

FWIW I recall seeing info that indicated wet blocks of NC(for safety) were detonated with the aid of a certain amount of dry NC and detonator.

If a forum search is done youll find a whole lot info concerning these very same topics regarding ETN etc posted by a Mr A./others Circa '03' on.
At that time his reccomendation was a melt cast - Accurate Arms #2-#5 DBSSP/ETN
"might be a good explosive""the suggestion for using sperical dbsp is because of high density and propogation considerations"
Axt qoute;its likely that molten ETN will also have some good colloiding w/NC.. ""..OB with about 5/1 ETN/NC and you should have a quick simple yet potent plastique"

Unfortunately it seems ETN has no solvent type effect on NC/DBSSP.So for whatever reason melting ETN was considered a safe? Method? to make a melt comp.Used or contemplated by Mr A,Axt and likely many others.

Who did the mysterious Mr A turn out to be?Ideas Roscoe?
Seems to me my post/OT was basically nothing that hasnt been talked about ad infinitum?So why the firestorm is above my paygrade.

[Edited on 13-2-2011 by grndpndr]

pjig - 13-2-2011 at 11:55

I would never feel comfortable melt-casting ETN into a dbsp.
:o

Why wouldn't you just reduce the dbsp with acetone or NM, then add the ETN till a plastic is formed? Melt casting something that sensitive seems like a death-wish IMO..

grndpndr - 13-2-2011 at 12:30

That was my thinking .The melt cast ETN/DBSP concept is the product of others imagination/experimentation.

Do a forum search for ETN composites youll find whose Ideas
all these practices can be attributed to.Im not one advocating melting ETN.But youll find several pages of different compositions using ETN.Both as a melt cast and as a acetone
DBSP/ETN mixture.Composites w/perchlorates etc .Including discussion of stabilizers such as diphenlamine,baking soda,urea etc.

[Edited on 13-2-2011 by grndpndr]

Rosco Bodine - 13-2-2011 at 12:36

FYI

Melt casting ETN is not my novel idea or invention and several examples are described in PATR .

As for the Mr. Anonymous aka Rosco Bodine matter ....
what is the problem there I really don't know

But what is a problem here in this forum with "new topics"
that are really old discussions being reposted .....
along with various non chemistry topic postings
which boil down to substantively being requests that
amount to "First, know I am an expert on explosives, however, will somebody please spoon feed me basic instructions 1-2-3 and ABC on the easiest way a non-technically educated person should proceed with basic manufacture" for whatever .....

and with that proposition I do have real problems and
this game I will not play

There seems to a lot of "kill the messenger bringing bad news" going on here just because I have said the MEKP and DBSP mixture is not a good idea. Well isn't that just too damn bad .....no "firestorm" .....just a matter of fact explanation. I am really getting weary of this kind of
"manufactured controversy" that really seems personal rather than technical.

Nitroesters and other nitroesters would probably be a happy mix if the stabilizer is mutually compatable with the component nitroesters. By experiment I found that the
diphenylamine doesn't fit that bill. If it makes you happy to think I have misidentified or lied about that .....then hell, believe what makes you happy.

[Edited on 13-2-2011 by Rosco Bodine]

The WiZard is In - 13-2-2011 at 13:11

Quote: Originally posted by pjig  
@ Rosco
What is your take on the old "nipolite " HE that was used as grenade?


Nipolite dobe in PATR2700 N27

PETN - NC- DEGDN - %c.


This from Google.com/books — do be most curious ....

http://tinyurl.com/4cgrfdy


djh
----
Organic Chemistry: The practice
of transmuting vile substances
into publications.

Anon.

grndpndr - 15-2-2011 at 10:24

I apologize for whatever animosity my posts may have generated.It was not my intent
to intentionally aggravate/bait or anything of the sort, no matter what the perception might be.I greatly respect roscoes knowledge and contributions.Maybe meaningless to some so FWIW once again my sincere apologys.I hope this can be the end of the matter as far as Is possible.

PS I would have PMed this sparing the rest of you but I was unable to U2U.

holmes1880 - 21-2-2011 at 19:45

Enough pointless arguing, gentlemen.
I still cannot figure out what to do with DBSP. I can't really press it inside the cap like ETN powder.....it presses in a bit, but then pushes back out. :mad:

Options:

1. Grind it down in a mortar for lower density.
2. Lightly dissolve it in acetone and poor it into a grain. ---I am uneasy about dissolving it, cause I don't know if it can disstabilize the NG from diphenylamine coating
3. Do nothing, use "as is" just pack into a small confining capsule- it is a gamble, since even the volume/mass of DBPS is great(3-5grams), it may actually be a less effective initiator than 300mg PETN that will be inside of it.

Uhhh.. stuck.

quicksilver - 22-2-2011 at 08:32

The issue boarders on the "practical application" of energetic materials which is a Forum restriction; that would be one big reason why few would venture from addressing the subject outside of a chemistry/science perspective.

There are several stabilizers in DBSP and depending upon the brand configuration. The binder material can vary from polyester to cellulose. There really can't be one answer that fits because of the commercial nature of the product and it's variances. However the likelihood of stabilizer separation is very unlikely unless the stabilizers are first placed in solution and separated from the binder. If there is no separation from the solvent solution the product would remain is it had been - albeit there is possibility of layering as in geological formations depending on density levels within a large level of solvent : this is very unlikely in instances where the material has not been reduced to a free-flowing liquid. Even in that case there is little likelihood of contamination to make this a problem.

Separation is possible if desired but it must be accomplished as a goal in itself and the appropriate solvents must be used to achieve that objective. Diphenylamine could be separated but not without a pointed effort. So could all the elements of DBSP or TBSP be separated; but reducing them via a plasticizing of the polyester would not do so.

[Edited on 22-2-2011 by quicksilver]

simply RED - 23-2-2011 at 01:59

DBSP or any kind of smokeless powder is absolutely impractical to use as a high explosive.

The only slightly practical solution of doing it is pour 10-20% pure nitroglycerine in it, mix extremely well, even if the powder does not dissolve (it won't in most cases). Use 10-20 grams PETN booster and good enclosing for this mix.

Don't try to dissolve it or anything like that, this just ends up in a big mess and no results can be achieved.

[Edited on 23-2-2011 by simply RED]

holmes1880 - 24-2-2011 at 07:10

^^^^^
Oh boy, somebody didn't read my first post.

DBSP sensitivity is what makes it so attractive as a BOOSTER material. Of course, no one intends to use it as main charges-it's too expensive anyways! As little as 0.2g lead azide (equivalent) will set off small quantities of DBSP. I don't even consider using more than 10g of DBSP in any application.

Bert - 24-2-2011 at 07:50

There is considerable documentation in Naoum: "Nitroglycerin and Nitroglycerin Explosives" on the German diversion of WWI surplus smokeless powder to use in the mining industry. Repeated mention is made of the need for strong initiation to prevent blown out shots. Long story short, it CAN be used in high explosives when strongly confined, but it isn't easy or economic unless you've got many tons that the treaty of Versailes prevents you using for the original purpose... There's a good reason that BATFE allows the US general public to buy and ship personal use quantities of smokeless powders without federal license and record keeping.

Look on YouTube under "videodemolitions" for a video Axt made years ago of lightly confined tests performed with several varieties of reloading powder initiated by commercial #8 caps.

[Edited on 24-2-2011 by Bert]

[Edited on 24-2-2011 by Bert]

quicksilver - 24-2-2011 at 10:46

Quote: Originally posted by Bert  
There is considerable documentation in Naoum: "Nitroglycerin and Nitroglycerin Explosives" on the German diversion of WWI surplus smokeless powder to use in the mining industry.


Indeed (pp 446, 450) Naoum makes a number of these issues very clear. His text is perhaps one of the definitive works of that period of history regarding the subject. His Supplement also provide bibliographic information wherein more information on the subject is defined.

On an off topic note, Naoum is also one of the better sources for understanding the use and production of the Nitrometer, it's importance historically & industrially.
These are some of the most significant reasons why both he & Davis should be read in depth.

gregxy - 25-2-2011 at 20:35

Smokeless powder is also difficult to ignite.

I have been working on a project to ignite it electrically.

I have one called "titegroup" from Hodgdon. It consists
of small flakes and the MSDS lists NC and NG. The ignition
temp is listed at 200C. I was happy to find that it is
graphite coated and conducts quite well. If I measure the
resistance with my ohm meter it comes out at about 3K for
a small pile.

To ignite it I tried using a 100uF cap charged to 300V, 4.5J of
energy. The powder did not ignite. Compare this to the
human body model for ESD testing 1500V @ 100pF or
around 1e-4J .

What seemed to happen was the current vaporized
the graphite forming a low impedance plasma. You could
hear it pop and see the fat spark passing right through
the powder. However the pulse seems to be so fast that
it does not heat the grains enough to ignite them.
I could zap the powder 2 or 3 times before it would stop
conducting. Later on I did succeed by placing a large
inductor in series to lengthen the pulse.

I think the grain shape is important. These grains appeared
to be made by flattening a ball powder. I suspect they
lack sharp edges which would be easy to heat to ignition.


[Edited on 26-2-2011 by gregxy]

grndpndr - 26-2-2011 at 02:45

The old bullseye DBSP also has flattened grains and apears to have a low density compared to a sperical grained ball DBSP.Thats just an empirical observation based on my own perception.
I could measure a repeatable volume of a variety of sp powders Including flake DBSP Bullseye,extruded grains of SP
IMR and DBSP ball powder.if that would alleviate any doubts?
Establish a sort of baseline?!:)

If the idea is to use the sp as a sort of electric squib Ive had good results softening the SP/DBSP with acetone as a solvent and applying 1/4gr or so to the nicrome itself.Ignition is near instant and and quite viqourous. :D
Adding a chlorate oxidizer and AL powder might make the squib quite energetic.

I recall that titegroup Pistol powder has almost the same content of NG as the old Hercules Bullseye pistol powder for all practical purposes ,37%NG versus near 40% for the bullseye equivalent.It would be interesting to know the density of the respective SP's

[Edited on 26-2-2011 by grndpndr]

[Edited on 26-2-2011 by grndpndr]

holmes1880 - 26-2-2011 at 09:05

Interesting observation about flatness of Bullseye grains and density. But I think that the grains themselves are very low density. Those are light as specs of dust.

gregxy - 26-2-2011 at 11:51

The density for titegroup is around 0.9g/cc
(this is sitting in the 1lb bottle)
It seems to be quite powerful, only 5gr are needed for
a Luger 9mm.

A nicrome wire does work well, just placed among the
grains and is fast if it is thin gauge like #36. I'd rather
ignite it directly since nicrome wires are fragile.

quicksilver - 27-2-2011 at 09:59

Quote: Originally posted by gregxy  
Smokeless powder is also difficult to ignite.

I have been working on a project to ignite it electrically.

(...........snipped for brevity)

To ignite it I tried using a 100uF cap charged to 300V, 4.5J of
energy. The powder did not ignite. Compare this to the
human body model for ESD testing 1500V @ 100pF or
around 1e-4J .



What you are dealing with has some well researched material behind it: however, it's not too easy to access. Please see USBOM Bulletin #59 C, Hall - "Investigations Into Electrical Detonation". This then leads to a rather lengthy trial during a period where Electrical Engineering was in it's infancy. Bibliography is provided in #59.

As a generality a stimulus needs to be in place to provide the need stimulus to allow for the (energetic material) to release heat through it's ("decomposition") so that one energetic stimulus is mandated to overcome a boundary for a given material to provide energy.

Heat to heat is often the least effective method if managed electrically - & here is where the challenge starts to form. Heat to provide a given stimulus is generally quite high or the energetic material quite sensitive as a DDT. Consider this example: the spit of a flame may not be nearly as hot as electrical discharge (in the case of C/D) however it exists over a greater period of time. The "spark" must be maintained at a longer time. One step away is the transference of energy (via a Joule dispersion) in the form of electrical pulse, etc. The "flame" will always beat it for time on the mark. Therefore the need for a greater level of energy and a wider dispersal area. Further still is the "EBW" concept that breaks down the given stimulus package (bridge-wire, etc): the discharge must be much more lengthy or much more powerful & here is where the complication begins with a given experimental material.

Many issues need to be studied to determine what will preform a given task and decisions need to be made as to best (most effectively) go about it. Some materials are VERY sensitive to direct electrical stimulus. Those that are more so are those that are at high risk via static release (PbN3, aluminised per/chlorates, etc). However there are those at the opposite end of the scale (nitrocellulose).

In industry the designs mfg for many "EBW" concepts are inverters with a well designed step up and they are (many times) used from a high current sources for both efficiency and portability (a truck battery as a starting point). The use of cap-discharge designs become very expensive and quite dangerous. To utilize these, the actual wire leads need to be able to effective and efficiently deal w/ high current & HV. They must be thick. For sake of safety and expense they often bed to be short and managed by encrypted transmission via small dedicated repeater stations.

To format experiments, the demand is for a "pulse" designed capacitor (bank). Even photo-flash capacitors may function (in a bank) for a stand-in. but for lengthy trials, the capacitor must be one that could handle continual "pulse" discharges. The current must be high enough so that it coincides with a certain energy dispersion formula (which I believe is in the documentation: but the end result is, it's fairly high).
Utilizing nitrocellulose is perhaps the toughest starting point.
This is also why the electrical generator (blast-box, push, pull, or twist) has been with us so long. It gives a high current output for a longer time with the simplest form of design. The same could be said of a "pull starter" from a lawn mower, ect.

Experiments conducted without rather sophisticated recording equipment is a real challenge. Nearly 80+ years ago there was a device where a "spoon-like" metallic device held a testing material and another metallic "probe" was raised and lowered toward the material resting in the "spoon". various amounts of electrical energy were tested to determine what would provide the need stimulus for some materials to detonate, others to deflagrate.

[Edited on 27-2-2011 by quicksilver]

The WiZard is In - 27-2-2011 at 12:17

Quote: Originally posted by quicksilver  
What you are dealing with has some well researched material behind it: however, it's not too easy to access. Please see USBOM Bulletin #59 C, Hall - "Investigations Into Electrical Detonation". This then leads to a rather lengthy trial during a period where Electrical Engineering was in it's infancy. Bibliography is provided in #59.

not too easy to access.

Google.com/books worked for me.

[Edited on 27-2-2011 by The WiZard is In]

quicksilver - 1-3-2011 at 09:05

@ gregxy :
Here are some of the actual technical work-ups on energy dist, design, & complementary. It's pretty much as recent as i have & hopefully should provide answers to a lot of issues.

Attachment: ccl3_electronics_detonation.pdf (337kB)
This file has been downloaded 1126 times

Ball milled smokeless powder

Katie - 22-4-2020 at 16:41

I will be attempting to ball mill Accurate Nitro 100 powder (the fastest double base I could find) and setting off the product in various ways (open flame, confined open flame, detonated, detonated while confined).

I plan to use ceramic media and a remotely controlled ball mill of course. Even then I’ll be at least 100 meters away and behind cover because I may basically be setting off a pipe bomb! For detonation I’ll try dextrinated lead azide, with and without an ETN booster, as well as NHN.

Ball milled smokeless powder

Katie - 26-4-2020 at 20:24

I’ve created a thread asking about the idea of ball milking smokeless powder and think it’s related to this. We all know smokeless powder is designed to burn slower via use of additives and particle shapes, so I wonder if density, sensitivity, and detonation velocity/pressure wave duration could be optimized if ball milled smokeless powder was wet pressed and dried?

Let me be clear that I have not tried ball milking smokeless powder and am unsure of the safety. Obviously lead or ceramic media will have to be used (and are used safely to ball mill black powder) but it’s not been tried. I am planning a serious of experiments with ball milled powder as soon as I can get to my vacation home and set up a remote ball mill outside (I have plenty of room to do this safely, and will proceed under the assumption that the ball mill will violently explode!)

I’ll add in a density experiment. Off the top of my head, I’m thinking of comparing unmilled powder, milled powder, pressed milled powder, and milled/unmilled powder mixed with microspheres you decrease density further than unmilled. The main obstacle I foresee is designing a reliable testing procedure that will be able to detect the likely small differences in performance.