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Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

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Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#41

Post by dvtrn »

giantg2 wrote: post #7

If you're going to play around with explosives, an old knowledgeable teacher is best. I imagine incompetence gets weeded out early. The guy in the video has been in quite a few others too. It's fun to see how the hosts are usually a little nervous and he's calm as can be.

"What makes me a good Demoman? Well if I were a bad Demoman, I wouldn't be sitting here discussing it with you, now would I?"

One of the silliest, hilarious but on point thing I've ever heard uttered from a video game character

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#42

Post by giantg2 »

Vladimof wrote: post #39
giantg2 wrote: post #21

Earlier quoted context omitted.

The explosive is stable (small cubes of most plastic explosive can even be lit on fire and act as fuel). But there is still danger in correctly handling/connecting the detonator. I'm not sure, but I thing the acceleration charge might be a less stable type as well (obviously they aren't going to give us step by step instructions).

> (obviously they aren't going to give us step by step instructions). nitrocellulose is very simple to make and detonate... and is also very stable.... I don't see why we need secrets... I played with that stuff when I was a teenager

Is that what they are using for the acceleration charge (not the main charge!)?

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#43

Post by natly »

londons_explore wrote: post #6

This is just a few dollars worth of copper and explosives. Attach it to a few tens of dollars worth of drone. (The cheapest drones are under 10 dollars now). A country could release 1000 of these and direct them at any military target, and they'll do massive amounts of damage at very low costs. Most anti-drone defences can be defeated simply with a redesign of the drone (eg. Use UWB for Comms, and have dual gyros and…

Not sure why you'd use drones rather than just tiny remote controlled model airplanes.

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#44

Post by AdrianB1 »

toomuchtodo wrote: post #36
Vladimof wrote: post #27

Earlier quoted context omitted.

I wonder if that's how Ukraine killed so many tanks

My understanding is that it’s poor design, storing ammunition in a ring within the turret which turns out is a poor location from an integrity perspective. The “Jack in the box” vulnerability. > The fault is related to the way many Russian tanks hold and load ammunition. In these tanks, including the T-72, the Soviet-designed vehicle that has seen wide use in Russia’s invasion of Ukraine, shells are all placed in a r…

The design is responsible for the catastrofic explosions that blow the turret off the tanks, not for the tank being penetrated. The penetration is achieved by making the missiles explode on top of the tank, defeating the thinnest armor versus frontal armor that has 60-100 cm equivalent in RHA steel (they are composite, so thickness is different).

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#45

Post by AdrianB1 »

KennyBlanken wrote: post #32

"I designed this, for, well, filling by the user. It means it can travel on airplanes and such" Presenter: "DIY shaped charges, of course " "Mmm yes" I get that he likely meant it can be shipped on airplanes and local explosives used for easier logistics, but it's amusing to hear an explosive munitions expert brag about designing something so it can be carried on airplanes. "This box, I'm pleased to tell you, is full…

It is just saying it is so stable and safe, it can be transported on a plane.

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#46

Post by climb_stealth »

Nextgrid wrote: post #31
Vladimof wrote: post #25

Earlier quoted context omitted.

> much like a jet of hot water melts through a block of ice cold water can cut through steel also... https://www.youtube.com/watch?v=v0NVOThRooE

Waterjet cutting uses water to propel a powder which acts as an abrasive, like an infinite stream of sandpaper. I don't think water by itself will achieve much.

Huh, thanks for mentioning this! I always thought it was just water with enough pressure.

It looks like pressure cutting with pure water exists but it is limited to softer materials. This page [0] has a fair bit of detail on it all.

[0] https://www.machinemfg.com/waterjet-cutting-guide/#Classific...

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#47

Post by berkut »

AdrianB1 wrote: post #40
Vladimof wrote: post #27

Earlier quoted context omitted.

I wonder if that's how Ukraine killed so many tanks

No, it has nothing to do with shaped charges; they are using missiles that explode on top of the tanks. Most armor of the tank is frontal arc, some on the sides, top armor is minimal, just a few centimeters, so it can be easily penetrated by explosions of these missiles or by aircraft cannon fire from platforms like A-10.

HEAT warheads (what NLAW has) is completely to do with shaped charges.

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#48

Post by AdrianB1 »

dragontamer wrote: post #30
alkonaut wrote: post #11

Earlier quoted context omitted.

Something that carries say 1kg for any distance, is a pretty significant drone. The Dji Mavic pro can carry 1kg and is around $1k. > I think the only reason we haven't seen this on the battlefield yet is that we haven't yet had a war between the right countries. But we will. There are videos every day of Ukrainian drones dropping shaped charges like the Russian RKG-3/1600 from drones. Ukraine even has special troops…

1kg is similar to smaller warheads in the AT4 anti-tank weapon. But AT4 is not reliable, only 400mm of penetration and tanks can have 500mm or 600mm of armor. (Or really, equivalent to 500+mm once special materials or geometry is factored in). To reliably kill a main battle tank requires a larger munition. Javelin is a 8kg warhead IIRC. This is because Javelin is tandem: two warheads. First warhead destroys reactive…

You ignore that AT4 is fired at the main armor, while drone dropped munitions hit the top armor that is just a few centimeters. The impact point makes all the difference.

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#49

Post by davesque »

daenz wrote: post #16

I'm not sure I fully understood the explanation. So the copper cone is turned inside out and turns into a pointed wire that drives into the target? How is it that this wire can continue through the 1ft of steel? Is the force of the explosion flowing through this wire/tube, like liquid in a straw? And somehow it can sustain this through 1ft of steel?

Here's a vid I found that seems to show a simulation of the effect: https://www.youtube.com/watch?v=CpVVGk2OfQQ

Re: Shaped Charges – Sheet of copper going through 1ft of solid steel (2010) [video]

#50

Post by Brian_K_White »

WhitneyLand wrote: post #34
nine_k wrote: post #20

Earlier quoted context omitted.

Update: this is incorrect . The cone becomes very hot stream of molten copper. It melts through the steel plate, much like a jet of hot water melts through a block of ice. This happens fast enough that much heat does not have the time to escape from the impact site, despite high thermal conductivity of metals. The high pressure created by the explosion keeps the jet compressed from sides, too, so it does not fragment…

It’s not molten, and heat plays no role in the penetration ability. This is a very common misconception. It’s simply focused kinetic energy that does it. The cone focuses the copper into a slug like object, and the slug becomes similar to an extremely powerful bullet.

So it's like that old picture of the grass straw driven through the telephone pole by nothing but hurricane wind?

The flimsy straw could do it simply because of how fast it was moving. The strength of the straw doesn't matter, simply it's mass, moving that fast, carries itself through, ie the leading edge is not being pushed from behind like a nail, more like a bullet with a string attached?

Setting aside the simplification, that probably the mass of the rest of the straw does play some part not absolutely zero, is that a reasonable way to conceptualize it?

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