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

  • 597 points
  • 9 days ago

  • @Vladimof
  • Created a post

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


@londons_explore 9 days

Replying to @Vladimof 🎙

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 use a camera for location instead of GPS).

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.

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@127 8 days

Replying to @Vladimof 🎙

If you look just at how small the shaped charge inside the NLAW is, and how the weapon works, I wonder why you wouldn't just put that shaped charge inside a $50 drone and fly it directly above the tank.

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@puskavi 8 days

Replying to @Vladimof 🎙

I feel like this is really all about acoustics

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@giantg2 9 days

Replying to @Vladimof 🎙

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.

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@scotty79 8 days

Replying to @Vladimof 🎙

What's pretty surprising is that explosively formed projectiles can have quite a range and can be aimed precisely.

Explosion of PTKM-R1 anti-tank mine that destroys the tank by targeting it from above:

https://img-9gag-fun.9cache.com/photo/a0ZMv2n_460svvp9.webm

I also read about some antitank missile that basically has two such auto-aiming charges and just releases them when it's above the targets and they aim and detonate forming projectiles that hit the tank(s?).

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@blip54321 8 days

Replying to @Vladimof 🎙

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

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@anfractuosity 9 days

Replying to @Vladimof 🎙

Dr Alford also designed water-lined shaped charges for disrupting IEDs - https://en.wikipedia.org/wiki/Sidney_Alford#Early_Inventions

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@nostrademons 8 days

Replying to @Vladimof 🎙

The Wikipedia article on shaped charges is fascinating:

https://en.wikipedia.org/wiki/Shaped_charge

The penetration distance is proportional to the diameter of the charge (counterintuitive; you'd expect the height), and can be up to 7x as large. So a ~5 inch charge shown in the film can penetrate up to about 3 feet of solid steel.

Also, all of our known defenses against shaped charged rely on the assumption that the same spot won't get hit twice. Composite armor breaks and deflects the geometry of the jet through its deformation; reactive armor relies on a mini-explosion to defeat the jet. This has interesting implications in a world of drones and precision-guided munitions, and in fact the Javelin missiles we've been shipping to Ukraine have double warheads, the first to destroy the armor and the second to destroy the vehicle.

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@somat 8 days

Replying to @Vladimof 🎙

Got to admit, I was hoping they would dig the copper jet out of the sand.

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@pueblito 9 days

Replying to @Vladimof 🎙

Now I want to look into 3d printed explosives

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@swayvil 8 days

Replying to @Vladimof 🎙

Bad ass.

Momentum trumps substance.

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@stjohnswarts 8 days

Replying to @Vladimof 🎙

lol I think I'm on a list now for watching that :)

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@samlader 8 days

Replying to @Vladimof 🎙

Interesting simulation of a shaped charge:

https://www.youtube.com/watch?v=qqMoFx0uwpo

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@Animats 9 days

Replying to @Vladimof 🎙

That's a nice explanation of how anti-tank weapons work.

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@staticassertion 8 days

Replying to @Vladimof 🎙

https://www.youtube.com/watch?v=dHfQYGGUS4U

Slow Mo guys using shape charges.

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@KennyBlanken 9 days

Replying to @Vladimof 🎙

"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 of explosives."

Oh man, this guy is a hoot.

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@javert 9 days

Replying to @Vladimof 🎙

If you were wondering what inspired the accents of fictional pirates and witches in movies and TV shows, now you know.

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@tshubbard 8 days

Replying to @Vladimof 🎙

Shaped charges are also used to create the holes (perfs) in wellbores prior to fracking. The shaped charges blast through 1/2 inch of steel pipe and then a foot or two of rock. Sand and water are then pumped through the holes to prop open the rock and allow oil, gas, and water to flow out with less resistance.

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@Maursault 9 days

Replying to @Vladimof 🎙

In principle, I think this is how we defeat invading aliens. Production value of this piece is interesting. It kind of seems like an infomercial for PE4.

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@etaioinshrdlu 9 days

Replying to @Vladimof 🎙

Is there a diagram of the setup? I find the video pretty confusing to watch.

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@daenz 9 days

Replying to @Vladimof 🎙

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?

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@emmelaich 8 days

Replying to @Vladimof 🎙

Appears to be from a series bbc.co.uk/bang

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@allturtles 8 days

Replying to @Vladimof 🎙

For anyone else who was intrigued and wanted to see more, I found the full documentary here: https://www.youtube.com/watch?v=k1_sMaMcLG8

Presumably this is of dubious legality, but I can't find any official way to view it online in the U.S., or any recorded media form you can buy.

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@hunter-gatherer 8 days

Replying to @Vladimof 🎙

In the US/Iraq war such contraptions were commonly referred to as EFPs (explosively formed penetrators). My platoon was once hit by a four-array EFP that was hung behind a cement wall (US forces would often line streets with barricades like this) so we couldn't see it. It went through the concrete wall, the humvee, and took some legs with it. Brutal things they were. We avoided prolonged truck excursions, but I remember we used to always sit with our arms and legs as staggered as possible--The thought being that if an EFP went through, you might get lucky and only lose one arm/leg instead of two. Of course it probably didn't help... but whatever.

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@supernova87a 8 days

Replying to @Vladimof 🎙

I amuse myself by thinking that Sidney Alford (the expert in the video, who by the way appears to have passed away last year) looked like, and was, the modern Grand Maester, conjuring up magical (but yes, destructive and terrible) explosives for the use by kingdoms against each other. He should've been given a cameo part in Game of Thrones...

I got onto the topic years ago when watching the Dambusters. Related to this, he also has a video showing how putting a simple tube/bag of water behind an explosive charge magnifies its force incredibly. I believe he started a company that built and sold explosives with such a water-fillable jacket that could be used to knock down doors by police forces.

edit: here's the water filled explosive knocking down a door: https://www.youtube.com/watch?v=_80gWlDQdHg

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@amai 8 days

Replying to @Vladimof 🎙

„Electric armour is a type of reactive armour proposed for the protection of ships and armoured fighting vehicles from shaped charge and possibly kinetic weapons using a strong electric current“

https://en.wikipedia.org/wiki/Electric_armour

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