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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]

#71

Earlier quoted context omitted.

I wonder if that's how Ukraine killed so many tanks

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 r…

All design is compromise.

The autoloader is a design decision: it replaces a crew member, so Russian tanks operate with a crew of 3 instead of 4. This makes Russian tanks smaller and lighter. Here's a size comparison of the T-72 with the Abrams: https://preview.redd.it/mtwtamct1t821.jpg?auto=webp&s=101442...

For the massed tank-on-tank actions it was meant for, this is good! Smaller targets are harder to hit, and T-72s were supposed to be fighting gun duels against M60s while crossing West Germany, so all the armor is in the front plate. Lighter tanks are cheaper, so you can build more of them, going from 4 crew to 3 means your limited pool of tankers can operate 33% more vehicles in the field. Classic cold war-era doctrine, hard lessons learned from WW2. https://www.rusi.org/explore-our-research/publications/comme... (It makes regular operations like tank maintenance or replacing damaged tracks way harder, but oh well, nobody ever said being Russian was easy)

Separately, there is no particular reason to think Abrams tanks wouldn't be vulnerable to the same weapons, if the Russians had that tank today and were fielding them in the same way they're operating their own tanks. Abrams also has light top armor and no ERA tiles on the roof. An anti-tank grenade dropped by a drone on an Abrams ammo compartment would mission kill it instead of killing the crew, but it would still be out of operation. AFAIK, no Abrams are equipped with Trophy in significant numbers, so it would be just as vulnerable to Javelin or other top attack ATGMs.

Tanks are vulnerable from the air, so you need air supremacy; vulnerable to artillery, so you need counterbattery suppression; vulnerable to man-portable AT weapons, so you need dismounted infantry combined arms; vulnerable to AT mines, so you need demining combat engineers, perimeter security so UKR spec ops can't cross lines and plant them, and military police so enforce civilian curfews. Russia is doing none of this, partly due to incompetence, and partly because they just didn't have a big enough force. (Desert Storm took just a hair under a million troops!)

If Russia had Abrams, but held all else equal, we'd still be seeing hundreds of flaming wrecks on the nightly news.

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

#73

Question: Is there a way to play with these things at home? Any pointers to DIY stuff?

You can find it by Googling around, but you won't find it on chemistry YouTube channels as YouTube cracked down hard on those. Even videos on making precursors to RDX or HMX (which can be used to make C-4) are banned.

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

#74
post #2

That's a nice explanation of how anti-tank weapons work.

If you want to know more - for example how the fuze even knows when to trigger and how it actually triggers the explosion - there is a good (lengthy) video about the M58 hollow charge rifle grenate and fuze design: https://youtu.be/_Xb1CoXLWHg?t=2514

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

#75

Earlier quoted context omitted.

Here's a vid I found that seems to show a simulation of the effect: https://www.youtube.com/watch?v=CpVVGk2OfQQ

It appears to rely on the copper’s ductility. Curious if a gold or silver shaped charge has been modelled.

I found https://apps.dtic.mil/sti/citations/ADA278191 which has this to say about gold:

>Hypothetical shape charge liner. High density is a benefit but equally low speed of sound indicate s that it may be no better than uranium. An advantage may be found in its ductility, if it leads to greatly improved jet formation relative to its cost.

It seems that sound speed and density are considered more valuable, so tungsten, zirconium, molybdenum.

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

#76
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?

A major part of it is that the copper is going extremely fast.

But also see other explanation, about being renewed.

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

#77
post #21

Earlier quoted context omitted.

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).

> (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

[deleted]

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

#80

Dr Alford also designed water-lined shaped charges for disrupting IEDs - https://en.wikipedia.org/wiki/Sidney_Alford#Early_Inventions

Am I reading this right? That section also says he made shape charges out of cucumber that could cut steel!
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