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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]

#111

Post by sudosysgen »

alkonaut wrote: post #11
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…

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…

Antidrone warfare is very very difficult. They are small and go slow and are thus difficult to shoot down. See how Iraqi militias fly drones into US bases and how Hezbollah regularly flies drone into Israel unpunished (sometimes Israel even has to resort to fighter jets to shoot them down).

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

#112

Post by CapitalistCartr »

itsyaboi wrote: post #100
jvanderbot wrote: post #65

Earlier quoted context omitted.

iirc, nothing is rigid, it's just very high energy jets, so they don't deform much. like particles in water jets cutting steel.

Fun fact: water doesn't actually do the cutting, the water is just a medium for carrying an abrasive dust (ruby/sapphire/diamond) that abrades the steel.

We use 80 mesh garnet.

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

#113

Post by GartzenDeHaes »

nine_k wrote: post #20
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?

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…

A plasma technically. And it doesn't exactly penetrate, it pushes the steel atoms aside very literally like sticking your finger in butter.

Edit: obviously it penetrates, but not in the way that you would expect.

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

#115

Post by stjohnswarts »

matheusmoreira wrote: post #106
mhh__ wrote: post #91

Earlier quoted context omitted.

The younger guy in this clip actually ended up retiring because he got brain damage in a contraption he designed for this show. https://www.bbc.com/news/uk-58762935

> The injuries happened when Mr Stansfield, who was 42 at the time, filmed a Bang Goes The Theory feature about the relative safety of forward and rear-facing child car seats. > The episode saw him "strapped into a rig like a go-cart which was propelled along a track into a post". I'm sorry but to me this reads like something out of Darwin Awards.

Exactly, this is what dummies (the inanimate ones), cameras, and sensors are for O_O

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

#116

Post by dylan604 »

GravitasFailure wrote: post #101
StringyBob wrote: post #80

Earlier quoted context omitted.

Am I reading this right? That section also says he made shape charges out of cucumber that could cut steel!

You read that right or we're both reading it wrong. I'm guessing the cucumber was an early prototype of the gelled water shaped charges, or he has a very...energetic...hatred of salads.

No, not salads. Spas.

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

#118

Post by chemeril »

blip54321 wrote: post #67

Question: Is there a way to play with these things at home? Any pointers to DIY stuff?

Yes and no. It's simple enough to construct a shaped charge from things you buy at Home Depot, assuming you have the right explosive. The explosive needs to be conformal (either plastic or castable) and capable of achieving true detonation. Secondaries like C4 and TNT are not easy to synthesize at home, and the primaries that are easy to synthesize at home are difficult to phlegmatize and handle safely at the necessary volumes.

Explosives are terribly fun but please do not try messing with them at home.

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

#119

Post by chemeril »

pueblito wrote: post #9

Now I want to look into 3d printed explosives

Several US national labs have been developing 3D-printed explosives technology for a bit now. Pretty crazy business that is (surprisingly) safer than doing large machining operations on bulk HE.

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

#120

Post by chemeril »

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

Nitrocellulose is not a high-order explosive and used nowhere in this experiment. Deflagration != detonation.
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