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Really. Melta bombs are so weird looking to me. They are used by planting them onto walls and stuff, but which way do they attach? Are they attached by the end of the bomb, or is that what those big squares on it are for, like magnetic clamps or something?
And how does one arm it? Do you just pull that levet like a pump, or is that handlebar supposed to be used as a sort of suction-cup clamp if the bomb attaches on the end?

Such a weird design... Even the Ork tankbusta bombs look more logical

The opposite of the handle end is magnetic and clings to vehicle surfaces... the handle is twisted and pushed inward to prime the bomb and start the countdown timer. It is basically a limpet charge.

They definitely have a magnetic component, though they probably have a variety of methods of attachment not just magnetism. Certain variations might use repulser fields, a patch of super adhesive, etc... Melta bombs aren't a single uniform design. There are likely thousands of Melta bomb variations.

from an explosive perspective, the closest thing I could compare them to in reality would be a thermobaric weapon, which are designed to create a much hotter explosion with a larger blast wave. however, this is more to create huge overpressure, followed by a return wave of negative pressure, used to flatten structures, so I'm not sure how this would be used to selectively melt metal in a breaching charge. To melt metal you'd have to use thermite or possibly a magnesium shaped charge. Reading the lexicanum on meltas aparantly they use some molecular petrol wizardry, which I assume is explained by being 'future technology'

I remember a very old conversion somewhere where a Marine was holding a Melta Bomb, the end of the Melta had unfolded creating a flat surface for them to adhere to the tank.

I've always pictured them as working in 2 ways:
- Twist the handle and the end unfolds, attach it to the tank and press the button on the handle and it does it's job but can be used again.

- Twist the handle the other way and it works like a grenade, pull the handle out and throw it at the target. Lets you use them at range but you cant reuse them.

 queen_annes_revenge wrote:
from an explosive perspective, the closest thing I could compare them to in reality would be a thermobaric weapon, which are designed to create a much hotter explosion with a larger blast wave. however, this is more to create huge overpressure, followed by a return wave of negative pressure, used to flatten structures, so I'm not sure how this would be used to selectively melt metal in a breaching charge. To melt metal you'd have to use thermite or possibly a magnesium shaped charge. Reading the lexicanum on meltas aparantly they use some molecular petrol wizardry, which I assume is explained by being 'future technology'

I always thought of it as a shaped fusion charge...

Mini reactor inside the bomb starts an unsustainable hydrogen fusion reaction and funnels everything forward at the point of overload.

 queen_annes_revenge wrote:
from an explosive perspective, the closest thing I could compare them to in reality would be a thermobaric weapon, which are designed to create a much hotter explosion with a larger blast wave. however, this is more to create huge overpressure, followed by a return wave of negative pressure, used to flatten structures, so I'm not sure how this would be used to selectively melt metal in a breaching charge. To melt metal you'd have to use thermite or possibly a magnesium shaped charge. Reading the lexicanum on meltas aparantly they use some molecular petrol wizardry, which I assume is explained by being 'future technology'

I though melta bombs and melta tech in general was about microwaves or something.

Looking at various wikis it seems to use fusion based radiation in a beam that melts all the things. so kinda close to microwaves.

functionally it seems super inefficient vs using that energy to propel and transferring the energy directly into a point. but then eh its scifi. it must use magnets to focus which is something that could be done.

id figure the melta bomb would basically need to be a directional blast charge like actual anti tank shape charges.

you magnaclap that puppy propa, prime it and it sends a jet of all the radiation directly into the tank.

Let me go get the best book ever written, the 2nd Edition Wargear book. A book so epic that my copy underwent mitosis and I somehow have two.

The melta bomb is a subatomic thermal charge capable of melting through heavily armoured targets such as fighting vehicles and dreadnoughts. A melta bomb is very bulky and must be accurately place so that its contact plate is touching the target. Melta bombs are used almost exclusively for siege/demolition work and close assaulting vehicles, being powerful enough to make a mockery of even the thickest ceramite or armourplas. The blast of intense heat generated by a melta bomb is entirely directed against the target so it has no blast marker.

So sayeth the holy tome of Wargear.

 Desubot wrote:

I though melta bombs and melta tech in general was about microwaves or something.

Melta Bombs are unrelated to Melta weapons from a technological standpoint. Its basically a shaped charge nuclear bomb. Both are named Melta because they melt their targets.

Fair enough. Nuclear explosions are a bit above my experience level. Although I will say a nuclear shaped charge wouldn't work. The metal of the shaped charge would be vapourised before the munroe effect that forms the molten jet even thought about occurring.

It's a real sledgehammer to crack a nut situation. Shaped charges only need conventional HE to function correctly. It's an effect that probably can't really be improved much further.

 queen_annes_revenge wrote:
Fair enough. Nuclear explosions are a bit above my experience level. Although I will say a nuclear shaped charge wouldn't work. The metal of the shaped charge would be vapourised before the munroe effect that forms the molten jet even thought about occurring.

It's a real sledgehammer to crack a nut situation. Shaped charges only need conventional HE to function correctly. It's an effect that probably can't really be improved much further.

It doesn't sound like it works the same way a shaped charge does. It's intense heat directed forward, so more like a blowtorch on steroids than an explosive.

It's a "shaped charge" in that the destructive effect is directed rather than radiating in all directions, that's all.

Also, it's not a nuclear fission of fusion reaction; as the original description states, it's a "subatomic thermal charge"; what does that mean? Nobody, including the bloke who wrote it, knows. The mechanism of meltaguns is similarly vague; microwaves get mentioned, but the main heating mechanism of microwaves is agitation of water molecules, which isn't the way meltaguns or meltabombs are depicted as operating, by melting large volumes of metal.

Meltabombs work the same way that Star Trek's Heisenberg compensators do; they work very well. They're basically magic thermite.

Yeah I assumed thats what you meant afterwards.

Its the usual sci fi dilemma, its sci fi tech, but then you need to try and explain it for books/media, and people with technical knowledge come and pick it apart.

It's just a generic fusion bomb that may or may not have a shaped charge, but is probably just an omnidirectional blast that outright vaporizes everything on contact. They're potent enough to fell buildings with just a couple or completely annihilate a tank.

just one of those generic fusion bombs an omni directional device would be wasted as a specific anti vehicle/fortification demolition charge. a focused charge (as opposed to a shaped charge, which is a specific type of device containing an inverted cone of copper or magnesium) would make more sense.

To be fair, GW are really making it a little too complicated. They couldve just based it on modern explosive science instead of trying to fancy it up with subatomics and all that nonsense. some sort of focused thermite esque compound projected through the target at high pressures.

 AndrewGPaul wrote:
it's a "subatomic thermal charge"; what does that mean? .

Something that sounds futurisitc without scientific background

But the closest you can get would be Thermite which is a mix auf Iron- and Aluminiumoxide powder that "burns" with 2500°C once ignited

Because it is a powder (and stable) it is easy to direct the reaction/temperature so its main use is for welding railway tracks
It was also used in WW2 in grenades for destroying artillery without the need of explosives


But basically a melta Bomb is similar to a Hafthohlladung https://en.wikipedia.org/wiki/Hafthohlladung containing a Shaped Charge (HEAT) and or something similar to Thermite

I always imagined it acted similar to thermite. Maybe it's more like a particle jet. which particle and how they're excited is anyone's guess?

Thermite is the only real way to melt metal explosively in the modern age, so that's the most reasonable thing to compare it with. However, thermite doesn't come contained in bombs. It comes in bags or blocks, and is applied directly to the surface that requires the heat.

To be fair it doesn't even make sense that they would use a melting charge instead of a conventional shaped charge limpet mine device, which would be much more effective against armoured targets.

 queen_annes_revenge wrote:
Thermite is the only real way to melt metal explosively in the modern age, so that's the most reasonable thing to compare it with. However, thermite doesn't come contained in bombs. It comes in bags or blocks, and is applied directly to the surface that requires the heat.

To be fair it doesn't even make sense that they would use a melting charge instead of a conventional shaped charge limpet mine device, which would be much more effective against armoured targets.

Which is why in my headcanon I see it as more of a shaped plasma charge.

From what I remember there are two ways in which melta weapons work. The first is the afforementioned 'subatomic agitation' method which works in some sort of science magic way.

The second (more plausable method IMO) is a mixture of two different chemicals mixing together to produce an extremely intense blast of focussed heat, sort of like a 'thermite gun'. This incedentaly is sort of a similar way to how plasma weapons work, just without the electromagnetic rails and electromagnetic containment field to turn the projectile into a longer range 'bolt' rather than a very close range blast/beam.

Meta bombs i Imagine use this second method of opperation, so its essentialy a super powerful high tech type of thermite bomb.

Depends on the melta bomb to be fair, as another post said there are variants, some are shaped charges while others are similar to normal explosives creating a cone effect or large area of destruction, I think it was primarchs Vulkan this had one even Make a large sphere hole in some wreckage, it could also possibly be that each one has settings for type of explosion.

 Formosa wrote:
Depends on the melta bomb to be fair, as another post said there are variants, some are shaped charges while others are similar to normal explosives creating a cone effect or large area of destruction, I think it was primarchs Vulkan this had one even Make a large sphere hole in some wreckage, it could also possibly be that each one has settings for type of explosion.

what do you mean by cone effect? do you mean an explosively formed metal cutting jet? because that's a shaped charge.

my thoughts on meltas and plasma are:

Plasma weapons work much like blasters in starwars (legends at least) - a volume of gas ionised in a chamber, spun as its left the chamber by magnets in the barrel forming a 'magnetic bottle' that holds it together, and breaks when it hits something releasing the plasma as a blast (range limit is due to it cooling in flight and the magnet failing.

As a contrast melta i see as working like our current plasma torches, a stream of hot ionised gas not unlike a very narrow flamethrower - not as stablised as the plasma guns, and so losing coherancy and heat faster for a shorter range, with a constant flow making them more dangerous close. Mentions of microwaves are either part of how they ionise the gas or a attempt to explain it to a lay audience (heats it like micowave does water) and promethium is the source of the gas and seem to simply mean fuel in gothic

the melta bomb could act in a similar way - a weapon that once attached (via magnets, glue, bad science) produces a pulse of high temp plasma directly onto the target, unfocused but directed into it - much like meltaguns but in direct contact. The effectiveness is probably limited by the amounts of fuel and power to ionise it.

Imagine a 40k "sooper science" version of this:

https://en.m.wikipedia.org/wiki/Nano-thermite

 queen_annes_revenge wrote:
Although I will say a nuclear shaped charge wouldn't work. The metal of the shaped charge would be vapourised before the munroe effect that forms the molten jet even thought about occurring.

You can absolutely make a shaped nuclear explosion. In fact, fission weapons sort of use shaped fusion charges. It just uses somewhat different methods than conventional explosive. But, also, even vaporized/plasma metal can absorb/redirect radiation that's a very large part of the weapon's energy release.

 queen_annes_revenge wrote:

 Formosa wrote:
Depends on the melta bomb to be fair, as another post said there are variants, some are shaped charges while others are similar to normal explosives creating a cone effect or large area of destruction, I think it was primarchs Vulkan this had one even Make a large sphere hole in some wreckage, it could also possibly be that each one has settings for type of explosion.

what do you mean by cone effect? do you mean an explosively formed metal cutting jet? because that's a shaped charge.

No I got the description wrong, it was a spherical shape around the bomb.

rbstr wrote:

 queen_annes_revenge wrote:
Although I will say a nuclear shaped charge wouldn't work. The metal of the shaped charge would be vapourised before the munroe effect that forms the molten jet even thought about occurring.

You can absolutely make a shaped nuclear explosion. In fact, fission weapons sort of use shaped fusion charges. It just uses somewhat different methods than conventional explosive. But, also, even vaporized/plasma metal can absorb/redirect radiation that's a very large part of the weapon's energy release.

A shaped charge specifically meaning the munroe effect which creates a penetrating molten metal jet used for anti armour purposes, is what I meant. A nuclear version of that would be pointless, unless you were trying to break into the emperors Palace, and had a shaped charge cone the size of a small starship.

Nuclear shaped charge equivalent. Nuclear weapon creating a highly directional weapon effect

https://en.m.wikipedia.org/wiki/Nuclear_pumped_laser

 Trickstick wrote:
Let me go get the best book ever written, the 2nd Edition Wargear book. A book so epic that my copy underwent mitosis and I somehow have two.

The melta bomb is a subatomic thermal charge capable of melting through heavily armoured targets such as fighting vehicles and dreadnoughts. A melta bomb is very bulky and must be accurately place so that its contact plate is touching the target. Melta bombs are used almost exclusively for siege/demolition work and close assaulting vehicles, being powerful enough to make a mockery of even the thickest ceramite or armourplas. The blast of intense heat generated by a melta bomb is entirely directed against the target so it has no blast marker.

So sayeth the holy tome of Wargear.

+1 for the source

+2 because I also somehow have two holy Wargear Books.