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Author: Subject: Unconventional Shaped Charges
Laboratory of Liptakov
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[*] posted on 17-1-2019 at 08:20


The bucket looks like he go through a war zone. Good Mad attempts......:cool:



Development of primarily - secondary substances CHP (2015) Lithex (2022) Brightelite (2023) Nitrocelite and KC primer (2024)
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[*] posted on 21-1-2019 at 03:57


Working on refining the liner geometry a "bit".....


Indicating the support to be dead centered, the rough liner after pressing (0,3mm thickness), the adhesive for fixing the liner to support:
IMG_3083.JPG - 91kB IMG_3084.JPG - 95kB IMG_3085.JPG - 103kB




Taking off the high spots with a really tiny cutter until an even surface is achieved:
IMG_3086.JPG - 68kB IMG_3089.JPG - 96kB IMG_3090.JPG - 96kB




After a bit of polishing the outer surface can be deemed worthy....also a glimpse at the black oxide coated holder I made for the cony bits to keep them from submitting to the call of the second law of thermodynamics (enthropy being the key word here :D )
IMG_3092.JPG - 77kB IMG_3096.JPG - 84kB IMG_3097.JPG - 93kB



A wee bit of heat helps to get the liner off the support without any troubles:


IMG_3098.JPG - 138kB



The arse end of the same support is machined to accomodate the concave image of the liner for a reversed seating and a matching cone in the tailstock shall support the copper while being glued to place:

IMG_3099.JPG - 91kB


Seems to turn out OK.....but the troubles began as I attempted to machine the inner surface flat. Seems that the seating was so perfect, the glue does not wick inbetween the surfaces and only holds the outer rim. Two times the liner came loose during machining...I gotta figure out something to rectify this:
IMG_3100.JPG - 87kB IMG_3101.JPG - 78kB

I am puzzled....that adhesive is like the devil when it comes to seeping between surfaces, even the tiniest microcracks are filled instantly and completely. And now it fails to the job....

[Edited on 21-1-2019 by markx]




Exact science is a figment of imagination.......
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[*] posted on 4-3-2019 at 23:13


In the spirt of Axt I would like to turn this thread in the direction of unconventional liner shapes if possible. Now, with 3D printing we can’t print any liner shape we dream of.


Does anyone have any documents or sources on active tamping, wave shaping, various liner shapes (tulip, fluted, swept, trumpet, bell, biconical, corrugated) that produce better penetration???

A former professor says he can grant me access to a 3D metal printer... so now that any shape (including thickness variations) is possible to manufacture... I am trying to determine which shape is the absolute optimum. My philosophy is to build on the shoulders of others... rather then reinvent the wheel

I plan to print the liner material from copper and print the wave shapers with plastic. Any shape of any complexity is possible.

Thank you! I am much looking forward to your responses.

[Edited on 5-3-2019 by MineMan]
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[*] posted on 5-3-2019 at 00:41


You can try the "x-charge": a classic cone liner with a mirroring cone waveshaper just behind it. The tips virtually connected. The cross section looks like a X shape....hence the designation. It was supposed to have greatly enhanced depth of penetration. For the life of me I can not remember where I read about this design. It was some kind of a document describing the developments of shaped devices in US military structures....

It is way more productive to cast the waveshapers from epoxy. Into molds formed from play dough. One can make numerous specimens in mere minutes. The original mold forming tool may be 3D printed if it is of a particular geometry.

[Edited on 5-3-2019 by markx]




Exact science is a figment of imagination.......
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MineMan
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[*] posted on 5-3-2019 at 18:58


Markx. You read that in “100 year history of shape charges”. They claimed to have accelerated EFPs to 6kms using the X Charge. Although little detail is given. For some reason, the current wave shapers I have seen are not mirror images...

A few months ago I saw a very complex waveshaper that was being modeled. It looked like symmetric claws... I can’t find that document anymore... it seems there has been a purge of this technology on the internet.

It sucks that I will only know the innovation of 40 years ago... it seems this material is home to so,e of the largest libraries... which are classified??
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[*] posted on 6-3-2019 at 01:18


Quote: Originally posted by MineMan  
Markx. You read that in “100 year history of shape charges”. They claimed to have accelerated EFPs to 6kms using the X Charge. Although little detail is given. For some reason, the current wave shapers I have seen are not mirror images...

A few months ago I saw a very complex waveshaper that was being modeled. It looked like symmetric claws... I can’t find that document anymore... it seems there has been a purge of this technology on the internet.

It sucks that I will only know the innovation of 40 years ago... it seems this material is home to so,e of the largest libraries... which are classified??


You are probably right, I remember there were a lot of historic descriptions of events represented in that book.

I know the "clawy" design you are talking about....if I recall correctly it was a novel approach regarding the formation of a large diameter jet that was almost equal to the diameter of the charge. Very complex approach from a technical side.

Old information is not of lesser value to the researcher, in fact I have often found the very opposite of that being true. And really for obvious reasons the contemporary discoveries in that field are not public knowledge nor will they ever be. So it is of little use to feel dissappointment about it :)
But on a generic level, given the emergence of destructive insanity that rises it's ugly head in the world, I fear that very soon we shall experience a major censorship ban on a great deal of information which we regard as being freely available. It shall happen quietly, gradually, in official denial of the fact and I feel it has already started. This process shall hardly be reversible in our lifetime and that truly is something that we should feel very much dissapointment about.




Exact science is a figment of imagination.......
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[*] posted on 6-3-2019 at 04:15


Quote: Originally posted by markx  

I fear that very soon we shall experience a major censorship ban on a great deal of information which we regard as being freely available. It shall happen quietly, gradually, in official denial of the fact and I feel it has already started. This process shall hardly be reversible in our lifetime and that truly is something that we should feel very much dissapointment about.


You are right.
This video was made by a friend: https://youtu.be/CMYEx4hEA3g

Before you say anything: the author is a chemical engineer, retired Navy EOD and now writes safety procedures for a refinery. So dont say he shouldnt touch it.

He made a wooden replica of that mine (shown at the end) for historical reasons, shared all the details with the World and... got a call from the authorities.

Apparently this could give bad ideas to bad people so he was asked to remove most information he had published...

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[*] posted on 8-4-2019 at 13:42


Greetings all. This be my first post though I've been lurking for quite awhile.

I've been bouncing around the interwebs in search for information referencing a shaped charge with cylindrical liner, but without much success. However today I found a patent that describes exactly that. Link below for those who may be interested.

https://patents.google.com/patent/US2988994A/en

-hellstrom

-btw, please feel free to correct me if I break any forum rules.
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[*] posted on 9-4-2019 at 15:11


Axt did try out a cylindrical liner here a long time ago. It's what got this thread going! But he's not active here anymore, and the design was just initiated from the back of the charge like most shape charges are. No special initiation points were used like they were in the patent.
https://www.sciencemadness.org/whisper/viewthread.php?tid=10...




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[*] posted on 10-4-2019 at 16:42


I'm putting together a simplified version based on the patent. Probably not unlike the one built by Axt. Images and results to follow.

-hellstrom
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[*] posted on 11-4-2019 at 01:20


Sweet. I have an idea for a conical/cylindrical hydrid.... I would be interested in large dia cylindrical because theoretical one could only have 1.5cm of explosives around the inner pipe if it is thin enough. 4 inch or larger would be interesting.
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[*] posted on 7-5-2019 at 22:33


All. See what complex wave shaping is capable of!!

https://www.researchgate.net/profile/A_Resnyansky/publicatio...

Now my question to you fellow scientist is the paper says aluminum makes the best penetrator for copper because it matches the impedance of the concrete target....

Can someone explain this?

I thought penetration was all about, jet length, density and velocity... once again I guesss Newtonian physics is over simplified
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[*] posted on 19-11-2019 at 02:48


How can working flexible shaped charge Semtex Razor ?

semtex_razor.jpg - 252kB
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[*] posted on 25-11-2019 at 12:58


Quote: Originally posted by specialactivitieSK  
How can working flexible shaped charge Semtex Razor ?



Could you re phrase your question? Are you asking how to CUT a SEMTEX linear shaped charge to a needed size, or how to use such a charge to MAKE A CUT?

Or something else yet again???

[Edited on 11-25-2019 by Bert]




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[*] posted on 28-11-2019 at 01:30


The flexibility. How can work flexible shaped charge without solid liner. What type of liner is used.
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[*] posted on 28-11-2019 at 11:02


I think these flexible linear shaped charges have thin lead liners which can be bent and shaped as lead is malleable in thin sheets.
The explosive filler would be a polymer or plasticizers based HE which allows for movement.
The outer case and standoff would be some sort of polyurethane or similar bendable plastic.




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[*] posted on 30-11-2019 at 07:18


To me, that looks more like a copper liner. I would think it is probably just annealed, but it is possible to make shaped charges with liners made from powdered metal such as copper or tungsten. If the powder was bonded in a rubber matrix, it would be possible to make a flexible shaped charge, though it wouldn't be quite as effective as a normal one with a solid liner.
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[*] posted on 2-12-2019 at 00:14


Quote: Originally posted by Microtek  
To me, that looks more like a copper liner. I would think it is probably just annealed, but it is possible to make shaped charges with liners made from powdered metal such as copper or tungsten. If the powder was bonded in a rubber matrix, it would be possible to make a flexible shaped charge, though it wouldn't be quite as effective as a normal one with a solid liner.


Why not as effective? Easier for the liner to collapse... jet could have the same momentum if the thickness is adjusted. I ask as someone who is interested in bonded metal liners.
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[*] posted on 2-12-2019 at 08:08


The density and speed of sound in the Cu-powder will likely be lower than in the solid, annealed copper. Also, since spinning the liner (on a lathe) from a plate reduces effectiveness due to the stresses imparted to the copper (it makes the jet spin), I am pretty sure that copper with lots of voids will produce a more "diffuse" jet.
Nevertheless, this technique is used in the oil industry to perforate the rock and allow the oil and gas to flow into the drilled hole. The powdered metal doesn't leave a carrot in the hole, so it is easier for the oil to pass.
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[*] posted on 31-5-2020 at 01:51


Main issue with cylindrical liner is that jet mass will be very very small and hence penetration will be very poor especially at large stand off. One will not get jet velocity equals to 2 times detonation velocity as collapse angle will never be zero.
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[*] posted on 31-5-2020 at 02:08


Quote: Originally posted by MineMan  
All. See what complex wave shaping is capable of!!

https://www.researchgate.net/profile/A_Resnyansky/publicatio...

Now my question to you fellow scientist is the paper says aluminum makes the best penetrator for copper because it matches the impedance of the concrete target....

Can someone explain this?

I thought penetration was all about, jet length, density and velocity... once again I guesss Newtonian physics is over simplified



Penetration to any target depends upon the impedance of penetrator and target. If penetrator impedance is larger than target, one gets maximum penetration with less lateral damage. This is the case for copper jet against concrete target. Now when we use aluminium liner, its impedance matches with that of concrete and lateral damage is more in such a case. Because aluminium jet deposits more energy in concrete than a copper jet during penetration.
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[*] posted on 31-5-2020 at 02:21


Quote: Originally posted by specialactivitieSK  
The flexibility. How can work flexible shaped charge without solid liner. What type of liner is used.


Lead is a good liner material for use in flexible linear shaped charges.




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[*] posted on 31-5-2020 at 02:39


Quote: Originally posted by markx  
You can try the "x-charge": a classic cone liner with a mirroring cone waveshaper just behind it. The tips virtually connected. The cross section looks like a X shape....hence the designation. It was supposed to have greatly enhanced depth of penetration. For the life of me I can not remember where I read about this design. It was some kind of a document describing the developments of shaped devices in US military structures....

It is way more productive to cast the waveshapers from epoxy. Into molds formed from play dough. One can make numerous specimens in mere minutes. The original mold forming tool may be 3D printed if it is of a particular geometry.

X charges and K Charges are not very effective in terms of penetration as compared to a conventional shaped charge at stand off distances of 3-4 calibers. These special shaped charges use less explosive quantity as compared conventional ones. Hence the contribution of total energy to penetration is also less. The moment one brings the waveshaper closer to the liner, tip portion of liner gets vaporised due to high incident angles of detonation wave. Then one needs to go for higher angle cones which naturally have lesser velocity. But then if one looks for large stand off applications, these shorter shaped charges may be of some help.

[Edited on 5-3-2019 by markx]
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[*] posted on 31-5-2020 at 02:50


Quote: Originally posted by greenlight  
I have been constructing a new 44mm EFP charge over the past weeks to try and punch a hole through a target that has resisted every attempt with a 30mm design.



The specs are:

▪Diameter = 44 mm
▪Flyer thickness = 1.5 mm Cu
▪Casing = PVC
▪Charge Weight = 26 g PETN PE (16% inerts)
▪Standoff = 95cm
▪Target = 20mm steel

I usually sight the charge with a high powered laser pointer which helps a lot as it is quite difficult to get a direct hit just by eyeing it. Of course the thing decides to shit itself today and makes sure it waits til I am at the test site to do it:P
The target plate is only the size of a dinner plate so it's a small area to hit but I sighted it by eye as best I could before inserting the cap and initiating it.
Walked back to ground zero and wow, shock and awe, it hit high;).

It is quite a decent hit though and quite a wide projectile due to the low head height of the charge. As can be seen by the photos, because it was so close to the edge of the plate it penetrated for a bit and then lost kinetic energy to the side as it took the path of least resistance and slid off over the top of the plate (that part was the top, plate was stuck in ground). You can also see stress fractures in the steel.



Also take into account the fact that it would have hit at a 10° angle instead of straight on, and the plate was just hammered into the ground and had some movement.
Penetration from what I can record is about 13mm before it started moving laterally. Im sure it would have almost if not fully made it if the hit was direct. Can always try some barrel tamping if not.

Guess I will have to step it up to a 50mm and have another crack at it, but first to find another decent laser pointer.




[Edited on 15-10-2018 by greenlight]

[Edited on 15-10-2018 by greenlight]


Experiments are fabulous. But there can be some improvements i feel. The flier thickness is too small for that caliber. It could be closer to 2-2.5mm. The deviation from the aim point could be due to break up of the projectile. Break up of projectile leads to a shift in momentum vector and deviation in its path. Also multiple hits are seen on the target. Best way to avoid this is to use a variable thickness liner.
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[*] posted on 22-6-2020 at 10:04


Thankyou..
The next variable to be changed was indeed the flyer thickness up to 2mm.
The projectile from that test did hit in one spot with minimal breakup, the other marks are from previous tests.
Unfortunately it hit on the very top and transferred a third of its energy off the damn plate:mad:





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