[HN Gopher] Shaped Charges - Sheet of copper going through 1ft o... ___________________________________________________________________ Shaped Charges - Sheet of copper going through 1ft of solid steel (2010) [video] Author : Vladimof Score : 117 points Date : 2022-05-14 21:01 UTC (1 hours ago) (HTM) web link (www.youtube.com) (TXT) w3m dump (www.youtube.com) | holly76 wrote: | londons_explore wrote: | 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. | qbasic_forever wrote: | Loitering anti-tank munitions are basically just that--a drone | with shaped charges that fire down. Russia actually has a mine | that detects the seismic profile of a tank rolling nearby, | launches a drone (of sorts) into the air, and shoots a shaped | charge right down into the tank (where there's very little | armor compared to the sides): | https://www.youtube.com/watch?v=zqtFhqSNubY | alkonaut wrote: | Something that carries say 1kg for any distance, is a pretty | significant drone. The Dji Mavic pro can carry 1kg and is | around $1k. | | > 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. | | There are videos every day of Ukrainian drones dropping shaped | charges like the Russian RKG-3/1600 from drones. | | Ukraine even has special troops specialized in it, the | Aerorozvidka (Google for the videos). | | The reason they apparently aren't bothered by anti drone | efforts is because the Russian forces don't seem to have the | training and equipment for it, so regular drones work well | enough (with selection bias of course - we don't see the videos | of the failed attacks). | | It's clear from that footage what an advantage it is to be able | to drop 2 or 3 munitions since you can correct for wind if you | miss the first, something you can't do with a single drop. | | The larger octocopters that can carry 5kg or more is probably | what you want for the job. Some range, and at least 2 charges | to drop. | dragontamer wrote: | 1kg is similar to smaller warheads in the AT4 anti-tank | weapon. | | But AT4 is not reliable, only 400mm of penetration and tanks | can have 500mm or 600mm of armor. (Or really, equivalent to | 500+mm once special materials or geometry is factored in). | | To reliably kill a main battle tank requires a larger | munition. Javelin is a 8kg warhead IIRC. This is because | Javelin is tandem: two warheads. First warhead destroys | reactive armor, 2nd warhead actually kills the tank with | 900mm of penetration. | | --------- | | For drones to be optimized on the battlefield will require | specially designed drones and special warheads designed to | fit in the cargo-capacity of drones. | | Switchblade 300 is nice for example but is too small to | reliably kill a tank. | | Switchblade 600 can kill a tank, but no longer has the small | and lightweight form factor that I'm sure the soldiers who | have to carry this crap care about. | AdrianB1 wrote: | 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. | formerly_proven wrote: | UA is literally dropping anti-tank grenades and other | explosives from commercial/civilian drones as we speak. | ChuckMcM wrote: | 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. | a9h74j wrote: | It's all fun and games until you realize your country has no | deniability about being at war with Russia. | natly wrote: | Not sure why you'd use drones rather than just tiny remote | controlled model airplanes. | Vladimof wrote: | Did you just upgrade the Slaughter bots? | https://www.youtube.com/watch?v=HipTO_7mUOw | | actually I think that you didn't because slaughter bots are | trying to not cause any collateral damage | giantg2 wrote: | 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. | h2odragon wrote: | Count the fingers. More than 8 is probably OK. age may be a | drawback, one gets too old to meddle with some of the more fun | things eventually. | Vladimof wrote: | This type of explosive is very stable... nothing like | nitroglycerin ... | giantg2 wrote: | 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). | Vladimof wrote: | > (obviously they aren't going to give us step by step | instructions). | | nitrocellulose is very simple to make and detonate... and | is also very stable.... I don't see why we need secrets... | I played with that stuff when I was a teenager | giantg2 wrote: | Is that what they are using for the acceleration charge | (not the main charge!)? | dvtrn wrote: | "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 | anfractuosity wrote: | Dr Alford also designed water-lined shaped charges for disrupting | IEDs - | https://en.wikipedia.org/wiki/Sidney_Alford#Early_Inventions | pueblito wrote: | Now I want to look into 3d printed explosives | [deleted] | a9h74j wrote: | Pro tip: you'll want to splurge on that second overtemperature | limit on your heated bed. | formerly_proven wrote: | https://3dprintingindustry.com/news/uk-defence-agency-plans-... | Animats wrote: | That's a nice explanation of how anti-tank weapons work. | Vladimof wrote: | I wonder if that's how Ukraine killed so many tanks | kube-system wrote: | Yes: https://en.wikipedia.org/wiki/FGM-148_Javelin#Warhead | KennyBlanken wrote: | Poor training, poor tactics, poor supply/logistics, poor | operational security. And despite Russia's supposed doctrine | of having very tight infantry/mechanized unit integration, | their mechanized forced have been very vulnerable to | Ukraine's infantry. Especially early in the war, Russia's | mechanized units were running out of food, water, fuel, and | ammunition. | | Russia used Ukraine's mobile network and cell phones, then | when they realized Ukraine was just targeting where they saw | lots of Russian phone numbers, they stole Ukrainian phones | off civilians...so Ukraine started accepting reports of stole | SIMs/phones and tracking those. | | Turns out that surrounding yourself with people who tell you | what you want to hear (and who are siphoning off every ruble | they can into their own pockets) isn't that great for having | a strong armed service. | | Also, you've got a force with a lot of conscripts who were | lied to about what they were doing, versus a force which has | watched their friends and family get butchered. That's one | reason you don't go around slaughtering civilian | populations...it makes for a very, very motivated, united, | angry enemy. | JumpCrisscross wrote: | We've also seen credible reports that where the reactive | armour is meant to have explosives, instead one finds egg | cartons. Corruption, through and through. | toomuchtodo wrote: | My understanding is that it's poor design, storing ammunition | in a ring within the turret which turns out is a poor | location from an integrity perspective. The "Jack in the box" | vulnerability. | | > The fault is related to the way many Russian tanks hold and | load ammunition. In these tanks, including the T-72, the | Soviet-designed vehicle that has seen wide use in Russia's | invasion of Ukraine, shells are all placed in a ring within | the turret. When an enemy shot hits the right spot, the ring | of ammunition can quickly "cook off" and ignite a chain | reaction, blasting the turret off the tank's hull in a lethal | blow. | | > For Russia, "the people are as expendable as the machine," | he said. "The Russians have known about this for 31 years -- | you have to say they've just chosen not to deal with it." | | https://www.washingtonpost.com/world/2022/04/30/russian- | tank... | AdrianB1 wrote: | The design is responsible for the catastrofic explosions | that blow the turret off the tanks, not for the tank being | penetrated. The penetration is achieved by making the | missiles explode on top of the tank, defeating the thinnest | armor versus frontal armor that has 60-100 cm equivalent in | RHA steel (they are composite, so thickness is different). | AdrianB1 wrote: | No, it has nothing to do with shaped charges; they are using | missiles that explode on top of the tanks. Most armor of the | tank is frontal arc, some on the sides, top armor is minimal, | just a few centimeters, so it can be easily penetrated by | explosions of these missiles or by aircraft cannon fire from | platforms like A-10. | berkut wrote: | HEAT warheads (what NLAW has) is _completely_ to do with | shaped charges. | AdrianB1 wrote: | Yes, but it is not how it is used in Ukraine. Quote: | "Against tanks and other armoured vehicles, the overfly | top attack (OTA) mode is used; the missile flies about | one metre above the line of sight, detonating the warhead | above the target's weaker top armour". | | It has dual-mode: direct attack and OTA. The many tanks | in Ukraine are killed in OTA, that does not use the | shaped charge effect. | KennyBlanken wrote: | "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. | a9h74j wrote: | YT brought me this[1] next, another jolly bunch with | explosives. | | One of them before an attempt with water between the explosive | and the target wall: I predict it will either go through or the | wall will be really clean. | | [1] https://www.youtube.com/watch?v=rUKTIt5GQrM | Someone wrote: | I interpreted that as him being able to bring everything except | for the explosives anywhere easily by regular airlines, where | he expects his client to provide the explosives. | AdrianB1 wrote: | It is just saying it is so stable and safe, it can be | transported on a plane. | javert wrote: | If you were wondering what inspired the accents of fictional | pirates and witches in movies and TV shows, now you know. | Maursault wrote: | 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. | etaioinshrdlu wrote: | Is there a diagram of the setup? I find the video pretty | confusing to watch. | Jabbles wrote: | https://makeagif.com/gif/shaped-charge-NMFryy | daenz wrote: | 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? | trhway wrote: | 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 everything in its way. | | A bit of current context - beside deep penetration the jet | isn't that destructive to surroundings. And here comes design | flaw of Russian tanks - getting inside a Russian tank such jet | frequently hits the tank's ammo which in those tanks is stored | in a carousel around/under the turret and thus it results in | the whole tank ammo explosion which even throws the multi-ton | turret several stories up into the air (you can see a lot of | the tanks blown up in that way - 'lollypops' - in Ukraine). To | compare - US Abrams tank has ammo stored in separate | compartment in the back of the turret. | KennyBlanken wrote: | 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. | Someone wrote: | Also crucially, the munitions compartment is weaker on the | outside of the tank than on the wall between it and the crew, | so if it goes, it blows out of the tank (search term "blowout | panels") | | Fireworks and ammunition factories and storage facilities | tend to have strong walls and relatively weak roofs for the | same reason: if a building goes boom, you don't want it to | make neighboring buildings go boom, too. | nine_k wrote: | The cone becomes very hot stream of molten copper. It melts | through the steel plate, much like a jet of hot water melts | through a block of ice. | | This happens fast enough that much heat does not have the time | to escape from the impact site, despite high thermal | conductivity of metals. The high pressure created by the | explosion keeps the jet compressed from sides, too, so it does | not fragment easily. | | Various kinds of "active armor" trigger the munition by a | thinner layer of metal well ahead of the real thick armor | plate, then produce counter-explosions to break the jet. | raldi wrote: | The video specifically says it's not molten. | causality0 wrote: | It's not actually liquid, it only behaves like one on impact | due to the magnitude of the forces. It's more accurate to say | it erodes through the armor instead of melting. | Vladimof wrote: | > much like a jet of hot water melts through a block of ice | | cold water can cut through steel | also...https://www.youtube.com/watch?v=v0NVOThRooE | Nextgrid wrote: | Waterjet cutting uses water to propel a powder which acts | as an abrasive, like an infinite stream of sandpaper. I | don't think water by itself will achieve much. | climb_stealth wrote: | Huh, thanks for mentioning this! I always thought it was | just water with enough pressure. | | It looks like pressure cutting with pure water exists but | it is limited to softer materials. This page [0] has a | fair bit of detail on it all. | | [0] https://www.machinemfg.com/waterjet-cutting- | guide/#Classific... | daenz wrote: | Sounds like pressure washing vs sand blasting. Only | difference between the two (aside from drastically | different effect) is sand blasting has an intake tube to | suck sand into the water jet. | Vladimof wrote: | you learn something new everyday | walnutclosefarm wrote: | Water is not doing the cutting there. Water is just the | carrier for garnet abrasive, which does the actual cutting. | Garnet is roughly three times harder than steel, so at high | pressure cuts it very effectively. | postalrat wrote: | Maybe that's what happens but the video explains it as a | stream of copper (not molten?) that pushes the steel out of | the way. | WhitneyLand wrote: | It's not molten, and heat plays no role in the penetration | ability. This is a very common misconception. | | It's simply focused kinetic energy that does it. The cone | focuses the copper into a slug like object, and the slug | becomes similar to an extremely powerful bullet. | Brian_K_White wrote: | So it's like that old picture of the grass straw driven | through the telephone pole by nothing but hurricane wind? | | The flimsy straw could do it simply because of how fast it | was moving. The strength of the straw doesn't matter, | simply it's mass, moving that fast, carries itself through, | ie the leading edge is not being pushed from behind like a | nail, more like a bullet with a string attached? | | Setting aside the simplification, that probably the mass of | the rest of the straw does play _some_ part not absolutely | zero, is that a reasonable way to conceptualize it? | davesque wrote: | Here's a vid I found that seems to show a simulation of the | effect: https://www.youtube.com/watch?v=CpVVGk2OfQQ | daenz wrote: | Great find @ 0:40. The only thing it doesn't convey very well | is the older man's explanation of the copper spear curling | outward on itself. From the simulation, it seems like it is | just punching through and maintaining its rigidity somehow. | JumpCrisscross wrote: | It appears to rely on the copper's ductility. Curious if a | gold or silver shaped charge has been modelled. | yread wrote: | It's not molten but it could be and it would still work as the | guy in the video invented water-lined shaped charges (for | disabling mines and IEDs without making them explode). What's | important is the force/pressure that pushes steel to the side. | daenz wrote: | Sorry to answer my own post, but I watched it again and picked | up on the key idea at 2:09. | | The inverted apex of the cone drives into the steel, pushing | the steel aside, but then the apex opens up and flows back | along the outside of itself. In other words, any given part of | this copper "wire" interacts with the steel only long enough to | push it open, then it is replaced by new copper. | | From this explanation, it sounds like the tunnel that has been | "bore" through the steel would be completely coated from start | to finish by the inverted copper cone. ___________________________________________________________________ (page generated 2022-05-14 23:00 UTC)