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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]

#241

Post by brazzy »

spiffistan wrote: post #206
sofixa wrote: post #203

Earlier quoted context omitted.

Interesting, thanks for sharing. A few things stand out (spoilers of course) - the Chairman of Deutsche Bank had an armoured convoy with two vehicles with bodyguards. It makes sense seeing that someone was trying to kill him, but outside of that context it seems a lot. Most European politicians, including heads of state and government, have less today. Second, he bled to death. I wonder what circumstances led to this…

Also rather interesting that Vladimir Putin is thought to have been involved as the RAF handler, if those sources are veritable.

> if those sources are veritable.

Those sources are pretty shit, honestly. One says the Red Army Faction claimed responsibility (this is not disputed). The other cites an (unnamed) "former Red Army Faction" claiming they had meetings with Putin, but makes no connection with the Herrhausen assassination.

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

#243

Post by andai »

dEnigma wrote: post #221
supernova87a wrote: post #150

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 thi…

>here's the water filled explosive knocking down a door Seems more like it's blowing a hole into a wall.

What wall? ;)

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

#244

Post by jacquesm »

davesque wrote: post #49
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

The time scale on those is very interesting.

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

#245

Post by jacquesm »

KennyBlanken wrote: post #28
trhway wrote: post #19

Earlier quoted context omitted.

due to the copper cone shape and the explosion wave propagation from the back the copper, which at those pressures is flowing like a liquid, is formed into a jet and pushed forward like a water in a power washer hose. Water at 3000bar would cut several inch steel ( https://www.youtube.com/watch?v=quL14Csmi_Y ). The copper in that explosion gets accelerated to the speeds of like 10km/s and as a result cuts through eve…

FYI, waterjets cut by using water to carry an abrasive media which is injected into the stream at/near the nozzle, not by the action of the water alone.

You can use an abrasive component but you don't have to, pure waterjet cutting works. And depending on the materials and the nozzle shape might actually be the optimum.

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

#246

Post by conradev »

sofixa wrote: post #203
hedgehog wrote: post #179

Earlier quoted context omitted.

Devious. The assassination of Alfred Herrhausen is I think the textbook example of this technique: https://en.m.wikipedia.org/wiki/Alfred_Herrhausen

Interesting, thanks for sharing. A few things stand out (spoilers of course) - the Chairman of Deutsche Bank had an armoured convoy with two vehicles with bodyguards. It makes sense seeing that someone was trying to kill him, but outside of that context it seems a lot. Most European politicians, including heads of state and government, have less today. Second, he bled to death. I wonder what circumstances led to this…

You have about three minutes for an arterial bleed. Perhaps less for two arterial bleeds. The proper technique would indeed to be tourniquet the legs, which you can do with anything (like strips of cloth) as long as you can make it tight enough.

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

#247

Post by magicalhippo »

earthbee wrote: post #189
hunter-gatherer wrote: post #136

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 remem…

EFPs are similar but distinct from shaped charges. Shaped charges use a conical liner that forms a jet that is only really effective over a limited range, the liner on EFPs is usually flatter and is designed to form a projectile that is effective over much wider ranges.

The dad of a childhood buddy was in our version of the rangers and mentioned they had made improvised shape charges (in his words) using a helmet filled with plastic explosives and a metal dinner plate as liner to form a shape charge.

When I got older I was thinking maybe he was telling some tall tales, but I guess this could work as an EFP.

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

#248

Post by aurizon »

jacquesm wrote: post #238
aurizon wrote: post #126

Earlier quoted context omitted.

When I was in college in Toronto in 1961 there was a surplus store. All manner of WW2 radios etc. I looked at one pile and it was about 15 rolls of primacord. This was a long 5/16 hollow tube of vinyl filled with pure TNT. It resembled rope = rope pile/ $3/roll of 100 feet. 2/$5. I knew what it was, so bought it all. it being worth $25-30/roll/ I was an Engineering stoont and Russia had just set of their Czar bomba.…

Active surplus?

Hercules Sales = sold Surplus on Yonge at Wellesley. The strip around there had Electro Sonic, Radio Trade Supply, Paramount Equipment and 2-3 small surplus and parts sellers. When transistor came along, radios never broke, TV's never broke and the parts and surplus ecosystem went away. Efrem Kohn came from Israel in the mid 60's and his Uncle Frank and Peter Eben who owned Active Machinery gave Efrem(Freddie) one of their store fronts = Active Surplus. He carried on until Queen W got gentrified and electronics from Taiwan and later China totally swamped Canadian electronics = all died off = no more surplus. The surface mount assembly also made parts salvage by hobbyists a waste for most people. Now there are only Creatron and one other place on College. I had 7 stores in 1985, closed the last in 2002. I was Parts Galore, a few remember me at trade shows, but I went into mining in 1995 and sold my company in 2018 and retired.

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

#249

Post by Retric »

earthbee wrote: post #189
hunter-gatherer wrote: post #136

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 remem…

EFPs are similar but distinct from shaped charges. Shaped charges use a conical liner that forms a jet that is only really effective over a limited range, the liner on EFPs is usually flatter and is designed to form a projectile that is effective over much wider ranges.

EFP’s are a type of shaped charge:

“An explosively formed penetrator, also known as an explosively formed projectile, a self-forging warhead, or a self-forging fragment, is a special type of shaped charge designed to penetrate armor effectively.” https://en.wikipedia.org/wiki/Explosively_formed_penetrator

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

#250

Post by treeman79 »

account-5 wrote: post #192
IMTDb wrote: post #186

Earlier quoted context omitted.

We call them : The Iraq War ( https://en.wikipedia.org/wiki/Iraq_War ) and the Russo-Ukrainian War ( https://en.wikipedia.org/wiki/Russo-Ukrainian_War ) This is a discussion about a special kind of explosive and a first hand story on how it is used in a conflict. Leave politics aside.

> The Iraq War was a protracted armed conflict in Iraq from 2003 to 2011 that began with the *invasion of Iraq by the United States–led coalition*... Whilst I agree that the preceding comments are off topic with their own inflammatory agenda's I do think it's important in generally acknowledging the war was caused by a US led invasion based on lies. Disclaimer: I fought there and lost people there, and after, but tha…

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