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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]

#221

Post by dEnigma »

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.

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

#222

Post by Retric »

somenameforme wrote: post #177
Retric wrote: post #145

Earlier quoted context omitted.

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.

The odds there are surprisingly high, but not better than even. 44.75%

It was a survivorship bias point but I didn’t make that clear.

I meant if you meet X people at a random point in their career then on average more than half will make it to the end because some of the original sample died before you sampled the population. Basically older people would have a lower chance of their luck running out even if they where all equally incompetent.

At least assuming the original population isn’t dying of something else vastly more often etc.

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

#223

Post by jhgb »

dragontamer wrote: post #168
nyolfen wrote: post #167

Earlier quoted context omitted.

> 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. So that the "shape" of the shape-charge points in the correct direction. they have been dropping 60's-vintage anti-tank hand grenades with 3d printed stabilizers: https://en.wikipedia.org/wiki/RKG-3_anti-tank_grenade#Histor... "220 mm penetration of RHA" which is plent…

> "220 mm penetration of RHA" which is plenty for top armor I seriously doubt that. Almost all modern tanks have reactive-armor on top. There's a reason why NLAW has 500+mm penetration AND top-down. NLAW is single-charge (no-tandem), to punch-through reactive armor requires a lot more penetration. Let alone lol Javelin with top-down, 900mm+ penetration, and tandem charge. I don't think 200mm or even 400mm is consider…

> Almost all modern tanks have reactive-armor on top.

Well it's good for Ukraine then that Russia doesn't really have a lot of modern tanks.

> Let alone lol Javelin with top-down, 900mm+ penetration, and tandem charge.

A Javelin can engage tanks directly if they're obscured from above of if the distance to target is insufficient for flying on a top-down trajectory, and for those situations it needs the 900mm+ penetration (otherwise the direct attack mode would be unusable and would not be provided as a feature). So you can't make the inference that because Javelin has 900mm+ penetration, top-down attacks require 900mm+ penetration.

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

#224

Post by denton-scratch »

jltsiren wrote: post #86
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…

Drones are effective, but nothing is ever cheap on the battlefield. While the warhead that ultimately kills the target is often cheap, the real cost comes from the system that picks the right target and delivers the warhead there at the right time. Cheap commercial drones have a short range. In order to use them effectively on the battlefield, each drone needs an operator, who must also be on the battlefield. Those o…

I envisage a swarm of say 50 cheap-ish drones with a "swarm leader", intercommunicating using some kind of short-range mesh radio. They'd be disposable, single-use. They could be launched by a squad of say, 10 men.

The swarm leader could be human-piloted or autonomous. Autonomy would be a matter of software and sensors; once you've invented it, it would be dirt-cheap to implement. A swarm of 50 would be enough to baffle air-defence systems capable of tracking multiple targets.

I have no idea if this exists, but it seems an obvious idea; if it doesn't exist, it must have been tried and found wanting.

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

#225

Post by denton-scratch »

natly wrote: post #43
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…

Not sure why you'd use drones rather than just tiny remote controlled model airplanes.

What's the difference?

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

#226

Post by giantg2 »

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.

The diagram shows a detonator and an acceleration charge. That's why I was wondering what the acceleration charge was.

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

#227

Post by mensetmanusman »

avereveard wrote: post #200
nyolfen wrote: post #166

Earlier quoted context omitted.

this is compounded by the fact that much of the armor on the ground in ukraine does not actually seem to feature the advanced defenses developed during the soviet era, like ERA. i've seen several photos of what appears to be decoy ERA on destroyed t-72's, which was nothing more than a hollow brick of steel. i suspect graft or a weak economy is the reason.

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.

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

#229

Post by mensetmanusman »

jimnotgym wrote: post #215
dvtrn wrote: post #41

Earlier quoted context omitted.

"What makes me a good Demoman? Well if I were a bad Demoman, I wouldn't be sitting here discussing it with you, now would I?" One of the silliest, hilarious but on point thing I've ever heard uttered from a video game character

It strikes me that if you work with modern explosives and follow sensible procedures like retiring to a safe distance, the risks to you are not that high. The risks in a demolition are huge, but not to the life of the explosives guy. I can imagine the job of weakening the structure, (by removing parts of it) prior to the explosives carry more risk to the operator

I don’t know. I’m a trained chemist and after enough years, you have that one day where you might’ve went to sleep too late and where you use the wrong type of glass, and a boiling vat of sulfuric acid etc. fails quickly and melts a bunch of stuff.

Sometimes I’m glad I’m in this field though, because I hear about the researchers working on prions that have started dying off, and I know it’s one of those one and 100,000 events that you inevitably experience.

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

#230

Post by 127 »

jade-m wrote: post #205
bottled_poe wrote: post #198

Earlier quoted context omitted.

The politics are important to understand, but it’s insensitive to bring this up in the context of an individual soldier’s account of this situation. Like, great work with the virtue signalling, you’re very clever and informed. Maybe try reading the room a bit and being a bit more compassionate toward people who have no influence in these politics?

I understand where you're coming from. But as an Iraqi who have lived through the "war" and having several family members and close friends who were killed in the war (all civilians), I can't help but consider the objectivity in naming here as insensitive to the half-million Iraqis who were killed in the war. Not to mention destabilizing the middle east forever.

What do you think about Saddam? If he was allowed to continue, would that not have destabilized the middle east? I'm not making an argument here, just honestly curious what you think about it.
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