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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]

#141

Post by [deleted] »

bawolff wrote: post #134
sophacles wrote: post #130

Earlier quoted context omitted.

But... in a field where being bad at your job is fatal, is it really a fallacy? Serious question - just like quoting an expert in the relevant topic isn't an appeal to authority, etc.

Its still a fallacy because some people are just lucky instead of being skilled, and its entirely possible to confuse the two. In the same way, an appeal to an authority is better than nothing, but its still a really weak argument. You can misunderstand authorities and authority can be mistaken or suborned. Its a reasonable argument if nobody knows much about the topic, but its never convincing if people are learned…

[deleted]

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

#142

Post by robocat »

htk wrote: post #131
matheusmoreira wrote: post #106

Earlier quoted context omitted.

> 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.

That’s why he was awarded around half of what he demanded, because BBC shared the responsibility by accepting the stunt, but he was also responsible for doing it.

> That’s why he was awarded around half of what he demanded

Which is why he asked for 4x what might be fair? I’m being facetious: I have no idea. I am just saying there is little constraint on how much damages you can reasonably ask for.

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

#144

Post by lazide »

chemeril wrote: post #124
giantg2 wrote: post #42

Earlier quoted context omitted.

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

It is not. Nitroglycerin doesn't have the capacity to detonate (necessary for triggering the main charge). Detonators (the acceleration charge you mention) are usually an explosive train starting with a sensitive primary like lead azide moving up to a secondary or pseudosecondary output charge like PETN.

Oh man lol. Nitroglycerin most certainly has the power to initiate even a insensitive explosive like RDX, PETN, etc. It's detonation velocity is ~ 7700m/s. It's just very unstable which is why it isn't used raw. A jostle or turning the stopper on the bottle it's in can set it off. The less pure it is, the more dangerous it is. It's detonation velocity is twice as high as lead azide for instance.

Nitrocellulose can also be detonated with a properly brisant primary charge, which nitroglycerin is quite capable of being.

Typically Nitrocellulose (aka gun cotton, and the primary ingredient in most smokeless powders) won't detonate on it's own, but it's a very different beast from nitroglycerin.

[https://en.wikipedia.org/wiki/Table_of_explosive_detonation_...]

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

#145

Post by Retric »

zhengyi13 wrote: post #138
bawolff wrote: post #134

Earlier quoted context omitted.

Its still a fallacy because some people are just lucky instead of being skilled, and its entirely possible to confuse the two. In the same way, an appeal to an authority is better than nothing, but its still a really weak argument. You can misunderstand authorities and authority can be mistaken or suborned. Its a reasonable argument if nobody knows much about the topic, but its never convincing if people are learned…

Luck eventually runs out. That's not to say you're wrong, only that I expect the distribution of the lucky amongst the skilled tends towards zero over sufficient time. "Beware old men in a young man's game."

Depends on how often you role the dice not just how bad the dice are. Someone that’s got a 1% chance of dying every fireworks show is extraordinarily bad at their job. But if they only put on 2 shows a year they have better than even odds of surviving a 40 year career.

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

#146

Post by nradov »

dragontamer wrote: post #68
AdrianB1 wrote: post #48

Earlier quoted context omitted.

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.

Sure, but Javelins (considered a very reliable weapon), is top-down AND 8kg of tandem charge of 900mm+ penetration. I think NLAW is ~500mm of penetration and top-down. Its not too hard to make a top-down weapon these days, but it does add weight to the device. -------- EDIT: I'm pretty sure that you can't just "drop" a mortar or AT4 warhead reliably either. You'd want to make it into the shape of... well... a bomb. S…

Mortar rounds are already the correct shape with fins to stabilize the flight path. Various irregular and insurgent forces have already weaponized the larger consumer drones with a rack that can release a single mortar round straight down. If the drone is hovering and there isn't much wind then the mortar round will fall straight down and detonate on impact. In some cases they may also have made minor modifications to the fuse mechanism in order to ensure reliable detonation when used in that mode. These weapons are very effective against lightly armored targets which lack effective air defenses or electronic countermeasures.

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

#148

Post by nradov »

a9h74j wrote: post #62
ChuckMcM wrote: post #14

Earlier quoted context omitted.

And you have just described the AeroEnvironment Switchblade 600 drone. According to Drive they haven't actually been deployed in Ukraine yet but they are on the list apparently. The smaller 300 has been deployed apparently but it doesn't carry a shaped charge, instead it carries an antipersonnel charge. More of a flying hand grenade kind of deal.

It's all fun and games until you realize your country has no deniability about being at war with Russia.

The Soviet Union never hesitated to supply weapons to North Vietnam when our country was at war with them. Turnabout is fair play.

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

#149

Post by relbeek2 »

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.

The calmness comes from really knowing and understanding what you are working with. I used to frequently work around hundreds of thousands of pounds of class 1 explosives. Once you understand that the primary risks of dry explosives are impact, shock, and impingement. You can protect yourself against those risks and get comfortable working around the material.

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

#150

Post by supernova87a »

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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