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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]

#251

Post by jacquesm »

aurizon wrote: post #248
jacquesm wrote: post #238

Earlier quoted context omitted.

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…

Super interesting, thank you for the backstory. I lived in Toronto from 1998 to 2003 and spent quite a bit time roaming around the dustier parts of AS.

Fond memories!

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

#252

Post by aurizon »

jacquesm wrote: post #251
aurizon wrote: post #248

Earlier quoted context omitted.

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…

Super interesting, thank you for the backstory. I lived in Toronto from 1998 to 2003 and spent quite a bit time roaming around the dustier parts of AS. Fond memories!

Yes, thanks. The Toronto surplus area was minuscule compared to Canal STreet in New York city in the 50's and low 60's. You might find some rabbit holes on google of the old days?.

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

#253

Post by jwhitlark »

giantg2 wrote: post #21
Vladimof wrote: post #15

Earlier quoted context omitted.

This type of explosive is very stable... nothing like nitroglycerin ...

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).

They used to burn c4 in Vietnam to heat coffee/food. Just don't step on it, as it suddenly remembers it's an explosive...

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

#254

Post by PebblesRox »

function_seven wrote: post #137
ethbr0 wrote: post #103

Earlier quoted context omitted.

Reading Ignition! convinced me that there's more than raw intelligence to experimenting with energetic chemistry. https://www.amazon.com/gp/aw/d/0813595835/

Note to anyone that might be tempted to get this as an audiobook: Don't! It didn't occur to me that the subject matter would be incompatible with narration, but it (IMO) just doesn't work that way. Large portions of the book have equations and heavy notation. Here's an actual passage: > it can be simplified to cee equals bracket two aitch over em end-bracket to the one half power times bracket one minus parentheses p…

Reminds me of a family story about my aunt recounting a Feynman lecture to her kids. She was drawing some diagrams he'd used and they said, "Wait a minute, how do you know what these looked like? Weren't you just listening to the audio?"

She realized that Feynman's verbal explanations were so clear that she had not had any trouble visualizing the diagrams as he drew and discussed them.

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

#255

Post by avereveard »

sofixa wrote: post #217
avereveard wrote: post #200

Earlier quoted context omitted.

the source of these pictures are all from ukraine. it's not far fetched to think they removed era and planted inert spacer to demoralize the enemy. in general, while the fog of war is in full effect, I wouldn't trust any one-sided intel.

How would fake lack of ERA demoralise the enemy when the enemy is getting destroyed anyhow, even if they have ERA? (And in your scenario, if it did have ERA)

invaders weren't being pushed back when the initial claims circulated.

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

#256

Post by avereveard »

mensetmanusman wrote: post #227
avereveard wrote: post #200

Earlier quoted context omitted.

the source of these pictures are all from ukraine. it's not far fetched to think they removed era and planted inert spacer to demoralize the enemy. in general, while the fog of war is in full effect, I wouldn't trust any one-sided intel.

That takes too much effort, also, Ukrainians know that if they went through all of that effort people would just say exactly what you are saying, so it’s doubly a waste of time And therefore a major risk for their lives.

what a silly, circular argument.

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

#257

Post by gpm »

jakear wrote: post #185
jade-m wrote: post #182

Earlier quoted context omitted.

I think you mean the US invasion of Iraq

Vouched for this. Names are important, it’s disingenuous to suggest US and Iraq played an equal role in initiating the engagement. Do we call it the Russia/Ukraine war or the Russian invasion of Ukraine?

Flagged this, I agree names are important, but the tone and context make this flamebait IMHO. I do think it's borderline.

I also don't quite buy the argument - see jhgb's reply - but that's definitely not why I flagged it.

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

#258

Post by sandworm101 »

magicalhippo wrote: post #247
earthbee wrote: post #189

Earlier quoted context omitted.

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.

That would totally depend on the metal. Some would just shatter. Too brittle a metal or too violent a charge and the 'penetrator' just becomes a shotgun of shrapnel flying out in all direction.

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

#259

Post by h2odragon »

blip54321 wrote: post #157
chemeril wrote: post #118

Earlier quoted context omitted.

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 necessa…

I'd like to mess with them at home, but not at "the necessary volumes" to go through a foot of steel as in the video. You know those little bang snaps you throw at the ground and they make a popping sound? For DIY, ideally, I'd do things in that kind of volume. I'd probably need a smidgen more, but I wouldn't want to do more than e.g. make a pinhole in 29 gauge sheet metal. What I'd really love to make -- but I don't…

Fireworks level explosives are fun and doable at the garage level. I don't think you can do real "shaped charge perpetrators" but you can do some really fun things like explosive welding and such.

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

#260

Post by amai »

„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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