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ManyInterests
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[*] posted on 9-4-2022 at 09:02


I would like to see those videos where the PiB is extracted from gloves, because I haven't been able to find them. The only PiB extraction video I have seen is from Liptakov's video where he extracts it from the tape.

Would the process be similar? Because if it is. I can get some gum and petroleum distillate (zippo lighter fluid) and try it in the next couple of days. I will also need to wash or at least chew the gum in order to remove the flavoring and sweeteners and stuff before washing it and trying it.
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[*] posted on 9-4-2022 at 11:38


I found this on Amazon. Turns out I should have also searched for polyisobutene in addition to polyisobutylene. I found that lip gloss base is basically made of almost pure PiB. I found these two products on amazon.

https://www.amazon.com/MakingCosmetics-Polyisobutene-1200-4-... (currently unavailable).

https://www.amazon.ca/PARAMISS-glossier-plumping-lipstick-ma... (available).

I looked through the ingredient list. I noticed that not only do they contain Polyisobutene, but also styrene. I did see videos from Liptakov where he dissolves styrofoam with toulene and acetone and then binds perchlorates to it.

Would that mixture work as is with a softener like bar and chain oil or 5W50 synthetic motor oil? I need an experienced opinion before shelling out cash!
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[*] posted on 9-4-2022 at 17:16


Wesson smith seemed to find the simplest solution
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[*] posted on 9-4-2022 at 17:20


Quote: Originally posted by MineMan  
Wesson smith seemed to find the simplest solution


True. I remember he made a plasticizer out of lithium greas... or was it titanium grease? I do believe during WW2 the Japanese had their own plastic explosive that was plasticized with wheel-bearing grease.

If that is all what is needed I can do that (with the lithium grease). Do I just add the grease dropwise and mix until the powder is all plasticized? Would a hair dryer or some mild heat source be needed to evaporate off some of the solvents in the grease be needed?
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[*] posted on 10-8-2022 at 20:20


So I'm back in the blasting cap business. I completed two batches (one is of better quality than the other) of NHN and just finished recrystalizing some ETN. I followed the instructions this time of using urea in the water solution (0.3% weight of ETN. I had around 1400ml of water. Far in excess of what I needed) after dissolving 19.2 grams of crude ETN in 30ml of warm (47 degrees C) acetone.

My crunchy ETN crystals are drying and I will weigh them as soon as all the water evaporates. Nothing fancy. Just air drying.

So I did look up wikipedia on ETN and they did mention that ETN can be hand pressed to a density of 1.2g/cm(3) with a slight risk of detonation. I know that Wesson smith had a video of himself using a hammer and a dowel to press his ETN even deeper, so I am probably exagerrating my fears of a detonation from hand pressing. Though you can never be too safe. I had an acid spill on my hand that now has resulted in scars that I will have to look at for the rest of my life. But they aren't impeding me in any way. I don't want to have any accidental detonations.

My question, however, is this: How do I calculate the density of g/cm(3)? My method for all the caps I created so far was just to add the ETN, and the with a wooden dowel (held with a pair of long-nose pliers) I would lower it gently until it would go no farther, then give a few gentle tamps. Then I would add the NHN in a similar manner and also gently press it. All done very gently with no major pressure exerted.

My new batches of NHN are VERY finely powdered, unlike my previous batches, which means I predict that when I press down on the NHN, it will be more compacted. My previous batches were rather thick despite manual grinding, so they were mostly immobile.

How would I measure it exactly? And when they say 'slight risk' of detonation, how slight are we talking about?
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[*] posted on 11-8-2022 at 03:22


To calculate pressed density:
- Measure the diameter of your cavity.
- Measure the depth of your cavity filled by your energetic that you want to calculated the density for. It is usually more convenient to measure the full length of the cavity, then measure the length remaining after the final press of your energetic. Then use these to values to calculate your length of pressed energetic.
- Use the length and diameter to work out the volume of the cavity that you have filled.
- Divide the mass you have pressed into the cavity by the volume of the cavity filled by the energetic and you have your pressed density.

On the pressing process
It is safer to press slowly with pressure than to impart high pressure with a swift blow.
Firstly, if you are using a length of dowel and hitting it with a hammer you need to be in the vicinity and it is hard to have protection between you and the material being pressed.
Secondly, a sharp blow is more likely to lead to conditions with the potential to cause detonation. Two to three joules is all it takes to detonate ETN, which is easily achievable with a hammer. Try it for yourself with a few milligrams, gloves, glasses and hearing protection.
Consider setting up a press, either mechanical or hydraulic, that you can measure the pressure you impart (either directly or indirectly) and that allows you to have some sort of physical barrier between you and what you are pressing.

If it is ETN you are wanting to press, you might also consider melt casting. This has its own dangers and needs to be thoroughly researched before you attempt it.
If you are light hand pressing you are not likely to get better than 1 g/cm3, melt cast will get you 1.6 to 1.7 g/cm3.
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[*] posted on 11-8-2022 at 03:26


Quote: Originally posted by ManyInterests  

So I did look up wikipedia on ETN and they did mention that ETN can be hand pressed to a density of 1.2g/cm(3) with a slight risk of detonation. I know
How would I measure it exactly? And when they say 'slight risk' of detonation, how slight are we talking about?


You can accurately calculate density by using a container of a known volume and weight, then weigh it after filling and measure the volume.
If you were to put a powder in a syringe and compress it with the plunger you can get a good idea of density by simply weighing it before and after filling and looking at how many CCs it compressed down to.
If you have 1cc of volume and it weighs 1 gram more than when it was empty you've got a density of 1g per CC.

As far as ETN detonating while pressing. I wouldn't worry too much, I've mechanically pressed it with thousands of PSI which is far beyond what a person could ever do by hand. You need to worry about the handling of your primary when assembling a cap much more so than something like ETN.
Still be careful and remember that it's peak forces in a localized area of the explosive that will get you, hammering it with a dowel is just flirting with danger, don't do that.
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[*] posted on 11-8-2022 at 06:55


Don’t use a hammer. Some batches of primary take sharp blows, others hardly a tap. Just. Don’t do it. These are the same insensitive primaries. Even the same batch will have crystals far more sensitive than the other crystals. There is zero need for high pressure pressing. Even the lightest pressing will be fine. Don’t make this more complicated or dangerous than it has to be. Don’t be a purist
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[*] posted on 11-8-2022 at 09:03


Quote:
To calculate pressed density:
- Measure the diameter of your cavity.
- Measure the depth of your cavity filled by your energetic that you want to calculated the density for. It is usually more convenient to measure the full length of the cavity, then measure the length remaining after the final press of your energetic. Then use these to values to calculate your length of pressed energetic.
- Use the length and diameter to work out the volume of the cavity that you have filled.
- Divide the mass you have pressed into the cavity by the volume of the cavity filled by the energetic and you have your pressed density.

On the pressing process
It is safer to press slowly with pressure than to impart high pressure with a swift blow.
Firstly, if you are using a length of dowel and hitting it with a hammer you need to be in the vicinity and it is hard to have protection between you and the material being pressed.
Secondly, a sharp blow is more likely to lead to conditions with the potential to cause detonation. Two to three joules is all it takes to detonate ETN, which is easily achievable with a hammer. Try it for yourself with a few milligrams, gloves, glasses and hearing protection.
Consider setting up a press, either mechanical or hydraulic, that you can measure the pressure you impart (either directly or indirectly) and that allows you to have some sort of physical barrier between you and what you are pressing.

If it is ETN you are wanting to press, you might also consider melt casting. This has its own dangers and needs to be thoroughly researched before you attempt it.
If you are light hand pressing you are not likely to get better than 1 g/cm3, melt cast will get you 1.6 to 1.7 g/cm3.


No hammering. I am also looking into melt-casting ETN since that wold seem easier and safer than pressing.

Quote:

You can accurately calculate density by using a container of a known volume and weight, then weigh it after filling and measure the volume.
If you were to put a powder in a syringe and compress it with the plunger you can get a good idea of density by simply weighing it before and after filling and looking at how many CCs it compressed down to.
If you have 1cc of volume and it weighs 1 gram more than when it was empty you've got a density of 1g per CC.

As far as ETN detonating while pressing. I wouldn't worry too much, I've mechanically pressed it with thousands of PSI which is far beyond what a person could ever do by hand. You need to worry about the handling of your primary when assembling a cap much more so than something like ETN.
Still be careful and remember that it's peak forces in a localized area of the explosive that will get you, hammering it with a dowel is just flirting with danger, don't do that.


So putting in my dowel and just slowly increasing pressure until it will go no farther is fairly safe? That seems like a simple deal. Though I guess I won't be able to reach max pressure that way. I am looking at melt-casting right now.

Quote:
Don’t use a hammer. Some batches of primary take sharp blows, others hardly a tap. Just. Don’t do it. These are the same insensitive primaries. Even the same batch will have crystals far more sensitive than the other crystals. There is zero need for high pressure pressing. Even the lightest pressing will be fine. Don’t make this more complicated or dangerous than it has to be. Don’t be a purist


Yeah, I won't use a hammer. I kinda realized that that idea is really stupid. I just used the hammering as an example because I did hear that WessonSmith used it. But I won't. I will find other ways.

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[*] posted on 11-8-2022 at 10:59


Melt casting ETN can be done very safely if you use some common sense.
A lot of people act like it's some death wish but it can easily be done remotely.
Just melt it in the container you plan to detonate it in to avoid having to pour it or manipulate it in any way while hot. A hot water bath and some shielding around it works fine.

Keep in mind that ETN has an oddly high critical diameter when cast. You might get inconsistent detonations with typical sized caps and you'll still have to press a little bit of powdered ETN on top for best results (though a powerful primary like NHN will likely work on its own anyway).
Also, it's best to allow it to slowly cool and harden over a long period of time, maybe 20 minutes or so. This is a good reason to use a hot water bath.



[Edited on 11-8-2022 by OneEyedPyro]
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[*] posted on 11-8-2022 at 12:44


When calculating the density of pressed charges, be aware that even moderate pressures will make the casing expand, which will have a significant effect on the result. So if you do it this way without a correction factor, you will over estimate the acgieved density.
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[*] posted on 11-8-2022 at 19:13


Quote: Originally posted by OneEyedPyro  
Melt casting ETN can be done very safely if you use some common sense.
A lot of people act like it's some death wish but it can easily be done remotely.
Just melt it in the container you plan to detonate it in to avoid having to pour it or manipulate it in any way while hot. A hot water bath and some shielding around it works fine.
[Edited on 11-8-2022 by OneEyedPyro]

That is definitely the best way. All you need is a container that can withstand the heat for a couple of minutes. You can litterally do this anywhere as long as you have hot water.

Quote: Originally posted by OneEyedPyro  

Keep in mind that ETN has an oddly high critical diameter when cast. You might get inconsistent detonations with typical sized caps and you'll still have to press a little bit of powdered ETN on top for best results (though a powerful primary like NHN will likely work on its own anyway).
Also, it's best to allow it to slowly cool and harden over a long period of time, maybe 20 minutes or so. This is a good reason to use a hot water bath.
[Edited on 11-8-2022 by OneEyedPyro]

As far as I remember on a paper posted here (cant remember the name) the researchers concluded that bigger ETN crystals obtained by melt casting were easier to set off than powder.




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[*] posted on 11-8-2022 at 20:54


Quote: Originally posted by Herr Haber  
[
As far as I remember on a paper posted here (cant remember the name) the researchers concluded that bigger ETN crystals obtained by melt casting were easier to set off than powder.


Sensitivity and critical diameter don't necessarily go hand in hand.
Most explosives are easier to detonate at lower densities where there are pockets of air within it. This is true even with liquid HEs such as when nitroglycerin forms bubbles.

I can certainly say that cast ETN is a good bit harder to initiate than hand pressed powder. With cast it's easy to get partial dets at small diameters.
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[*] posted on 12-8-2022 at 00:03


Quote:
Melt casting ETN can be done very safely if you use some common sense.
A lot of people act like it's some death wish but it can easily be done remotely.
Just melt it in the container you plan to detonate it in to avoid having to pour it or manipulate it in any way while hot. A hot water bath and some shielding around it works fine.

Keep in mind that ETN has an oddly high critical diameter when cast. You might get inconsistent detonations with typical sized caps and you'll still have to press a little bit of powdered ETN on top for best results (though a powerful primary like NHN will likely work on its own anyway).
Also, it's best to allow it to slowly cool and harden over a long period of time, maybe 20 minutes or so. This is a good reason to use a hot water bath.


Yeah, I did some research on melt casting and asked a few questions on a discord server. I was informed that putting the cap with the ETN in a hot water bath for a few minutes should be sufficient to melt it. That is what I plan on doing.

I can't shield it unfortunately. I will put it in a pyrex container and heat the water to 70C in my heating mantle. The body I am using for a blasting cap is the same old Bic round stic pen that I used previously. I tested the pen body in much hotter water and nothing happened to it, so it can easily tolerate the 70C necessary to melt the ETN and keep detonation risk to a minimum.

Quote:
That is definitely the best way. All you need is a container that can withstand the heat for a couple of minutes. You can literally do this anywhere as long as you have hot water.


The container I will be using is the same pen body that I used in all my blasting caps. It is made of plastic, and I heard that it is not a good conductor of heat, so the process might take longer than normal. But I got time to wait and I will observe it. After which I will obviously let it cool down at the most leisurely pace before adding anything else to it.
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[*] posted on 12-8-2022 at 05:49


The risk of detonation should be pretty much zero but anything between you and the container wouldn't be a bad idea, even a cutting board or something securely propped up in front of it. Glass fragmentation wouldn't be much fun, on that note why not just use a sturdy metal container like a steel cooking pot and heat the water on a stove first before adding the cap? A mantle isn't really necessary.

[Edited on 12-8-2022 by OneEyedPyro]
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[*] posted on 12-8-2022 at 10:34


Quote: Originally posted by OneEyedPyro  

Sensitivity and critical diameter don't necessarily go hand in hand.

Agree with that.
Quote: Originally posted by OneEyedPyro  

Most explosives are easier to detonate at lower densities where there are pockets of air within it. This is true even with liquid HEs such as when nitroglycerin forms bubbles.

I would have said that is true especially with liquid HE's sensitive or not.
I also agree that *most* explosives are easier to initiate at lower densities.
Not all ;)

Quote: Originally posted by OneEyedPyro  

I can certainly say that cast ETN is a good bit harder to initiate than hand pressed powder. With cast it's easy to get partial dets at small diameters.

What is a small diameter ? I think the paper I mentioned anvil tested molten blobs vs loose powder, cant recall the diameter and weight.
I guess it also depends on how good an initiator your primary is and how much you're using, the length and diameter of the column of your secondary and the strength of your casing.
I never thought about the inner diameter of the pens and syringes so many people seem to be using. Something loosely based upon the specs of commercial products will definitely work with melt cast ETN though.

@Manyinterests:
If you're worried about the operation do it outside in your garden. Or in the nearby forest.
Use a thermos flask, a stove or several candles to heat water in a soup can. Remove when the water is boiling, put your thingies in and come back 30 minutes later.
Good thinking on the heat conductivity of plastic. If your setting allows it you can come back periodically, add hot water and leave again. It can overflow as long as the open end if your pen is above the container level.
For extra security, if your casing fails I would recommend putting a smaller container submergered at the bottom of your soup can.




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[*] posted on 12-8-2022 at 10:43


I am pleased to announce that my attempt at melt casting ETN in a plastic pen body has been a great success! It not only went off without a hitch, it turned out that the pen body was an adequate conductor of heat as to fully melt the ETN into liquid in just 7 minutes of being in the water bath at 70C.

I loaded my pen with 0.5 grams of ETN, melt-cast that one, added a further 0.3 grams on top it after it fully soldified and then added another 0.3 grams of NHN as a primary. I found a large amount of space above it near the electric match, but I think I cut it a little short, though the epoxy does appear to have covered it entirely and formed a solid plug, so I hope it is OK.

I also placed a small bit of plastic cling film between the ETN and the NHN. Because in previous blasting caps I made, I noticed some degradation of the ETN that greatly reduced its power. I wasn't sure if it was left over acid or some chemical incompatibility with the NHN. But either way, the thin layer of plastic will act as a barrier, but hopefully not reduce the explosive power of the cap.

I am going to monitor it for a few months before setting it off. I just want to see if it will go bad like the previous ones.

IMG_20220812_112041804 - Copy.jpg - 1.9MBIMG_20220812_112058827 - Copy.jpg - 2.2MB
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[*] posted on 13-8-2022 at 13:32


Quote: Originally posted by Herr Haber  

What is a small diameter ? I think the paper I mentioned anvil tested molten blobs vs loose powder, cant recall the diameter and weight.
I guess it also depends on how good an initiator your primary is and how much you're using, the length and diameter of the column of your secondary and the strength of your casing.
I never thought about the inner diameter of the pens and syringes so many people seem to be using. Something loosely based upon the specs of commercial products will definitely work with melt cast ETN though.


I'd say around 7 or 8mm is where cast ETN can be erratic if not initiated strongly enough. Just my experience.
I've used lightly pressed ETN powder in those little stirring straws you get at the bar which are probably around 1mm ID and they detonate every time with just a spec of SADS on top.

I'm sure confinement plays a role here like you said.
Funny enough my failed dets were with Bic pen caps very similar to ManyInterests, even with pressed ETN on top I had a few partial dets.
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[*] posted on 13-8-2022 at 19:59


Quote: Originally posted by OneEyedPyro  
Quote: Originally posted by Herr Haber  

What is a small diameter ? I think the paper I mentioned anvil tested molten blobs vs loose powder, cant recall the diameter and weight.
I guess it also depends on how good an initiator your primary is and how much you're using, the length and diameter of the column of your secondary and the strength of your casing.
I never thought about the inner diameter of the pens and syringes so many people seem to be using. Something loosely based upon the specs of commercial products will definitely work with melt cast ETN though.


I'd say around 7 or 8mm is where cast ETN can be erratic if not initiated strongly enough. Just my experience.
I've used lightly pressed ETN powder in those little stirring straws you get at the bar which are probably around 1mm ID and they detonate every time with just a spec of SADS on top.

I'm sure confinement plays a role here like you said.
Funny enough my failed dets were with Bic pen caps very similar to ManyInterests, even with pressed ETN on top I had a few partial dets.


Failed to detonate how? I never had a failure to detonate in my pens. I only detonated a few of them though (they tend to be loud and I need to find the right time and place to set them off). My first detonator was very powerful and detonated very well. My 2nd and 3rd detonations were very weak. I think it was due to the degradation of the ETN. At the time I wasn't sure why, but now I am certain that it was because I didn't wash away all of the acid correctly. Also I learned that simply recrystallizing ETN will not remove all the acid right off. The bulk of the acid must be removed before hand before any recrystalization is attempted. And even then, you can never give ETN too many water washes.

I practiced making a lot of detonators with black gunpowder before I did anything with high explosives. I had to learn how to properly seal the top and find what works and what doesn't. I realized that 5-minute epoxy is very good, but you need to get a nozzle attachment with a mixer in order to extrude the epoxy correctly. Also the nozzle is very thin and the head will go into the pen body to pour the epoxy directly into the cavity.

For this single test cap I made (Like I said, at least one month or two of monitoring before detonating it) I fear that I cut the top of the cap too short and I may not have had a good solid plug. It might still work, but the next time I try I will keep more on the top so I can fill it completely with epoxy.
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[*] posted on 14-8-2022 at 00:26


Mine failed because the cast ETN was at too small a diameter and not initiated strongly enough. It began to detonate at low order and basically blew itself apart rather than properly detonating.
Partial, low order detonations are common with a lot of HEs under those circumstances.
Nothing to do with impurities or reactions between the ETN and primary I assure you.
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[*] posted on 14-8-2022 at 19:09


Ahh OK. The diameter of the bic round stic pen is roughly the same as of commercial/military blasting caps, so I shouldn't have a problem with that. But good to know that you do need a good diameter for them to work properly.

It's been a few days and nothing has changed in my blasting cap. On this thread I did mention that I noted degradation of the ETN almost immediately after making the cap. So far it's been a couple of days, almost as much as the first cap I made and there is no change. I think I got me a winner! :D
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[*] posted on 15-8-2022 at 08:58


Quote: Originally posted by ManyInterests  
Ahh OK. The diameter of the bic round stic pen is roughly the same as of commercial/military blasting caps, so I shouldn't have a problem with that. But good to know that you do need a good diameter for them to work properly.

It's been a few days and nothing has changed in my blasting cap. On this thread I did mention that I noted degradation of the ETN almost immediately after making the cap. So far it's been a couple of days, almost as much as the first cap I made and there is no change. I think I got me a winner! :D


Commercial caps pretty much all use pressed RDX which has a critical diameter of about 1mm, cast ETNs critical diameter is probably about 8mm from what I've personally seen but others say 5mm.

They also generally use an unnecessarily large amount of lead azide as the primary instead of NHN and an aluminum tube rather than plastic.

I'm not sure how fast NHN undergoes DDT or its critical diameter but I know it's not nearly as fast as lead azide or as small of a CD, it's certainly a lot more powerful though.

The size of your cap is roughly the same as a commercial #8 but that's where the similarities end. With all that said I'm thinking they'll work.

Dr. Liptakov is the God of caps on the forum, funny he hasn't commented on your design.
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[*] posted on 16-8-2022 at 03:38


Critical diameter of pressed charges is inversely dependent on density (the higher the density, the lower the critical diameter). This is a bit counter intuitive since the sensitivity to initiation is greater in low density charges. Melt cast charges can't be assumed to be equivalent to a pressed charge of the same density.
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[*] posted on 16-8-2022 at 05:46


Quote: Originally posted by Microtek  
Critical diameter of pressed charges is inversely dependent on density (the higher the density, the lower the critical diameter). This is a bit counter intuitive since the sensitivity to initiation is greater in low density charges. Melt cast charges can't be assumed to be equivalent to a pressed charge of the same density.


I've found that with ETN the critical diameter is smaller at low densities, cast doesn't seem to have stable detonation below about 8mm and it's not for lack of a strong enough initiation.
Lightly pressed powder will detonate consistently at pretty tiny diameters though.
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[*] posted on 17-8-2022 at 02:01


I'm sure that the critical diameter of ETN is quite low, even at low density. Note, however, that it is not impossible to detonate an energetic below its critical diameter. It just won't be a stable self-propagating reaction, so in a very long charge, the detonation won't propagate all the way to the end.
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