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Author: Subject: Unconventional Shaped Charges
Axt
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[*] posted on 27-9-2005 at 19:52


I prefered to use the neck of the case to hold the liner, as its designed to do. No problems with aligning the liner centre, and the neck becomes the standoff so the liner is held firmly against the target on detonation. Though I can see how charging the case with explosive would be easier by going from the other end.

Liquids would be easier but NG wont fire satisfactorily in such small quantities, a thin past thats extruded out the the back when the liner is inserted may be the best charging technique.

Picture repost:



In this case it was a .303 fmj (180gr?) in a .308 case, and a 50gr in .22 K-hornet.

Buy some ring magnets and glue them around the case, easy fitting to target :P

[Edited on 28-9-2005 by Axt]
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CD-ROM-LAUFWERK
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[*] posted on 28-9-2005 at 03:34


thank you guys, but where can i get hollow bullets??
i dont think that it is the easyst to get some ammunition in germany.... :(
wicked!
i need liners :mad:

[Edited on 28-9-2005 by CD-ROM-LAUFWERK]
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Fulmen
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[*] posted on 28-9-2005 at 09:19


Quote:
Originally posted by CD-ROM-LAUFWERK
thank you guys, but where can i get hollow bullets?


Melt the lead out of the bullet. Don't know how it's done in Germany, but it should be possible to buy reloading components like bullets and cases without any permits. Just say you want to make some dummy rounds for display purposes.
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[*] posted on 28-9-2005 at 09:28


Easy loading was an important reason for my method, in addition the performance should be better since the effective length of the liner is greater. But it does require a steady hand or prefferably a guide of some sort to center the liner.
As for the standoff, I simply use three long screws taped to the shell, this makes it easy to fine-tune the legs to make it stand straight.

Standoff.jpg - 62kB
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Axt
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[*] posted on 28-9-2005 at 21:08


The .45 with magnet. These hold 2.5g PETN/NG, the .357 holds 1.3g. Standoff is provided by straight section of bullet, so it rests directly on the target. I typically dont use electric dets, Its perfectly legal for me to use fuse initiated SC's, not electrical ones, but they do look cooler :cool:

Anyhow, now that I see this is a competition to see who makes the nicest looking ones :P



[Edited on 29-9-2005 by Axt]
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Fulmen
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[*] posted on 30-9-2005 at 02:15


Raising the stakes, are we? Well, you've got yourself a deal buddy. May the best man win :-)
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FPMAGEL
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[*] posted on 6-10-2005 at 01:33


"Anyhow, now that I see this is a competition to see who makes the nicest looking ones", you meaning design or pics.

Hi you old folk, i've been working on high tensile penatration test and got some good results with petn, but i can't reach a depth of 3cm. Ji thinks the copper sheet is to thick for a standed fillar charge. Any one got some infomation or experience with more than 3cm, thanks.
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Axt
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[*] posted on 6-10-2005 at 06:34


Quote:
Originally posted by FPMAGEL
you meaning design or pics.

I was joking. Anyone can draw a picture but making one thats functional & practical is something else.

The rest of your ambiguous post makes no sense through lack of information. Same goes for your other incomprehensible posts today. Try making sense and putting it in some form of context :mad:

"3cm" with what? who the hell is "Ji"?, "too thick" is how thick?, "standard filler charge" umm yeh that means nothing to us.

It doesnt take much of a SC to penetrate 3cm, even the tiny ones above approach or surpass that. The glass liner I posted before (first page) pushed through and beyond 5cm.
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Fulmen
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[*] posted on 12-10-2005 at 10:52
Does size matter?


Me thinks it does. Forgot to mention it earlier, but I happen to have this little beauty lying about. It's an 76mm copper cone from a FFV552 trainer round for the 84mm Carl Gustav, complete with the dummy explosive charge taken from the round.

Now all I need is 500g of RDX to set it off :-)

552-liner.jpg - 83kB
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Axt
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[*] posted on 13-10-2005 at 19:38


Heh, yes. Size matter if one has the balls to set it off. I've been looking for an excuse to use one of these, foot wide hemispherical liner derived from a copper egg beating bowl.

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Fulmen
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[*] posted on 13-10-2005 at 23:49


Axt, you know you're insane?

BTW, let me know when&where this will be set off so I can be there :-)


--
There's a fine line between genious and insanity. You're it! -Close personal friend of mine.


[Edited on 14-10-2005 by Fulmen]
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[*] posted on 21-10-2005 at 01:49


"Well, here's a drawing of the charge I mentioned in my previous post. The case is a spent 30-06 (a 308 should work just as well), the liner is the jacket from a 147grs FMJ. Explosive was Comp C (RDX + 10% heavy oil) and standoff 20mm. "
To improve that don't make the liner so deep.

A test if the plate that has a hole in it is has a nice cut hole and flat, that was a good SC, if it is dented then it relied to heavyly on mass and speed not enought on heat.

""3cm" with what? who the hell is "Ji"?, "too thick" is how thick?, "standard filler charge" umm yeh that means nothing to us. "
fillar charge, something 5000ms+ det velocity. I was talking about Jim, sorry. Just thought people could help with the none usual stuff.

AXT that picture didn't have a good charge, it should have a nice cut, it relied on the liner speed to cut, you need the liner to heat up to 3000C or close to, that liner was still solid all over, you need the edges plasma, and the middle solid




[Edited on 21-10-2005 by FPMAGEL]
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[*] posted on 21-10-2005 at 02:28


Sorry to rain on your little parade, but you have no idea what you are talking about :P

It has been proven that the average temperatures of copper liners when fired with HEs like PETN or RDX are usually between 400-500 C. Never, even close to 3000 C. Shape charges do not “heat up to 3000C or close to” to “cut” through metal. I strongly suggest you read up on the phenomenon which is “the Munroe Effect”.
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[*] posted on 21-10-2005 at 02:51


Can a copper jacket bullet peice a bullet proof vest. No damn i guess because of a hardness material, interlaced with high tensile strength. Ok can you please explain why. My reason, kintic energy(speed,mass)= heat, hardness of liner on Tank armour, .Pleasesss

[Edited on 21-10-2005 by FPMAGEL]
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[*] posted on 21-10-2005 at 03:02


". I strongly suggest you read up on the phenomenon which is “the Munroe Effect”."
Thats a fucking HEAT charges not a shape charges.
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Axt
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[*] posted on 21-10-2005 at 04:14


FPMAGEL, did what I say before come across as an insult? Good, it was meant to but you certainly learn nothing from it. Its not hard to pick someone who likes to pretend he knows more then he does. It irritates me when people post erraneous informaton when they know themselves that they dont know what they are talking about, who are you trying to fool?

Start at the beginning of this thread and read. Everything you have said is wrong. I've posted direct references to studies on jet temperatures of copper liners.

Sorry dude, HEAT as in "high explosive antitank" are typically a shaped charge utilising the munroe effect. Why didn't you look up "munroe effect" on google before posting, its really that simple :mad:
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FPMAGEL
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[*] posted on 21-10-2005 at 13:42


http://en.wikipedia.org/wiki/Munroe_effect
"Explosive energy is released directly away from (normal to) the surface of an explosive, so shaping the explosive will concentrate the explosive energy in the void. If the void is properly shaped (usually conically), a high-velocity jet of plasma will form."
but in this thread they say it doesn't, not to be offisive but i just don't know what to think from this thread.

http://en.wikipedia.org/wiki/Shaped_charge
yeah nothing new.

[Edited on 21-10-2005 by FPMAGEL]
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[*] posted on 21-10-2005 at 14:09


Anthing wrong with this explaintion

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[*] posted on 21-10-2005 at 16:55


Quote:
The enormous pressures generated cause the target material to yield and flow plastically. A common misconception is that the penetration is a result of melting, but both jet and target usually remain in a solid state.


Anyway, wiki is not as reliable as research documents. Everything you claim has already been covered and has been proven flase numerous times by said sciencetific documents.
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FPMAGEL
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[*] posted on 21-10-2005 at 17:33


"Start at the beginning of this thread and read. Everything you have said is wrong. I've posted direct references to studies on jet temperatures of copper liners. "
And i didn't say that the whole liner is plasma, the liner can be 500C, but the edges(10th mm) can 1000C, and its the leading edges of the liner that touch the traget first.

"munroe effect" i read a coulpe of sources,still don't understand, is it that a vacum speeds up the explosive gases like with nuke warheads designs, or that pan cake/rod thing i was talking about early

[Edited on 22-10-2005 by FPMAGEL]
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Axt
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[*] posted on 21-10-2005 at 17:44


Yes, this argument has already been made in this thread. The temperature studies I gave on the second page are detecting the surface temperature of the jets, thus the "vapour skin" is false. The pressures generated are massive (in the order of 1 million atmospheres) since this is far higher then the yield strength of copper (1500 atm) and steel (10000 atm)the liner will flow as a liquid, but it isnt liquid. A glacier flows as a river, because of high pressures!
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[*] posted on 21-10-2005 at 19:43


Thank you, i understood that.
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[*] posted on 22-10-2005 at 22:53
Wall Strength


How drastically does teh strength of the SC casing effect the penetrating power of the device? Would there be a huge difference between say PVC and steel casings?
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Axt
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[*] posted on 23-10-2005 at 02:11


See attachment. In summary, yes the thicker the casing the better but overall the added weight makes for a less efficient charge, gram for gram the light containment will penetrate further but gram for gram of explosive the heavy containment will penetrate further.

What this actual gain is, as a percentage isn't mentioned.

Also with thick containment the liner should be held as firm as the body, no point constructing a SC out of 5mm steel pipe and then sticky taping the liner in.

[Edited on 25-10-2005 by Axt]

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[*] posted on 24-10-2005 at 00:18


Thankyou for the reference Axt. How would you suggest attatching teh liner into the pipe without malformation of the jet occuring?
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