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[Hanslanda]

I would think .75 caliber gyrojet HE rounds would be more effective than modern guns. O.o

[GiglameshDespair]

Lasguns are roughly equivalent in power to autoguns, but in fluff and general crunch. Here gives an autogun with a calibre of 8.25, which roughly equivalent in size to old ww1-2 rifle cartridges (so more power than modern assault rifle cartridges, especially with wahtever fancy future chemistry they use).

The amount of energy in a lasgun powerpack is never really stated anywhere in real measurements that I can see, so if you have that anywhere I'd be interested.

It's mentioned a powerpack for one kind of lasgun has 19 megathules. How much is a thule? No one but the god-emperor knows.

Taking it as future-speak for megajoules would give a powerpack 19000000 J. Sixty shots is 316,666J each so approximately 17.5 times the power of a .50 BMG.

Flashlights indeed. Probably not quite that strong.

 

[NullForceOmega]

No, not once you run the numbers as compared to all other equipment, the only baseline possible is to compare like to like within the setting and that makes everything in 40k laughable for shit that's supposed to be the product of a (fallen) mega-tech civilization.

That's one of the reasons I was so very disappointed by the results of the calculations.

Edit: also, I should probably point out I did those calculation when I was about seventeen and had way too much time on my hands, the crunch and fluff have been changed in the intervening time.

[GiglameshDespair]

I must admit then if you're comparing stuff against each other in universe I really don't see where you're pulling any hard figures from.

[NullForceOmega]

Because there are items in-universe that are easily comparable to real-world analogs, like the Vanquisher cannon.

Edit: By baseline I meant that once I was able to find the analog for a few weapons (like the cannon) I had to figure out what the numbers (power) meant.

[GiglameshDespair]

Because there are items in-universe that are easily comparable to real-world analogs, like the Vanquisher cannon.

...Or a 8mil rifle catridge, perhaps.

[NullForceOmega]

I didn't have the internet or unlimited money, I had to make do with available codices and what I could find from surfing the internet from my school's computer lab EIGHTEEN YEARS AGO, and lo and behold, none of the sources I could reach had anything like an actual caliber for the autogun.

Edit: Let alone a series of documents about an obscure experimental German munition from W.W. II, as the munition we are discussing is a caseless form, not a full bullet and shell.

Further edit: I'm not trying to be combative here either, I stated that the crunch and fluff have changed in the intervening time, and it is definitely possible that I missed something when researching that would have changed the equations.  But I've got twenty pages of math on every single factor I could find as a point of comparison, and that showed that overall 40k's weaponry would be right about equivalent to modern weapons of similar class, so if you have better data then by all means I'll accept refutation of my numbers.

I'm not a ballistics specialist, I don't have a degree in physics, and I've only studied laser technology passively, so I will fully admit that my knowledge is limited.

Even further edit: Okay, there is straight up no such thing as an 8.25 mm caseless munition outside of the autogun, you cannot use that as a point of comparison to anything real world, we have no concept what it's ballistics, powder load, configuration, or any other point of reference look like for determining anything useful beyond it being a solid-shell ballistic weapon of roughly equivalent power to other large-caliber battlerifles.  And designing the munition from the ground up as a thought experiment amounts to baseless supposition and is therefore not even remotely useful.

[GiglameshDespair]

8mm mauser was what I was referring to. It was literally one of the most popular military cartridges in its day, being the ammunition for the service service rifle for Germany in both world wars, but that's besides the point. _{Before you say "But that was 7.92×57mm!", the actual name of a cartridge is generally only tangentially related to what the cartridge actually is.}

The point I was making was that you dismissed my comparison to real-world analogues in favour of... a real-world analogue, which seems a tad dubious by itself. Where are you getting that the Vanquisher is literally a Abrams 120mm in every way that matters? And how does that correspond with the power of a lasgun?

You might have done twenty pages of maths, but it sounds nonetheless you compared apples to oranges and got a square as a result. All the calculations in the world don't help if you start from bad data, and I'm unconvinced there is any real data to base it off, fluff and crunch changes or no.

[NullForceOmega]

8mm mauser is a cartridge gig.  You cannot compare a cartridge to a caseless, they have radically different mechanisms, we therefore have no basis of comparison beyond extremely broad strokes.

And there have been multiple descriptions of the Vanquisher, in fluff and crunch, that straight up call it a 120mm smoothbore which uses APSD even the lexicanum (tho' it lacks an actual caliber) states that the weapon is a "smaller caliber" cannon without rifling, and that one of the two munitions it fires is a high-density dart submunition contained within a lightweight body that falls away in flight.  So to my purposes that would be a damned good base point to work from, the rules of aerodynamics and gravity don't change based on size, the same factors are at play whether it's a cannon round or a shotgun shell (BTW, shotguns in 40k are canonically 12 gauge, that would make them an extremely easy point of comparison wouldn't it?  I know that it is one that I used), and knowing the factors that define those things lets you easily back build what certain things mean from a mechanical standpoint.  Knowing the energy output of a weapon as compared to another weapon will then easily allow you to form a comparison.  So what If I had to determine footpounds of force then convert to joules and then compare based on other weapons within the setting to come to a conclusion, that's why it took twenty pages.

All of which is definitely overthinking such a ridiculous kitchen sink setting as 40K, but again, I was seventeen and had entirely too much time and nowhere near enough intellectual stimulation.

Edit: we might also be having a bit of a miscommunication here, up above I was responding to Hans, not you, I didn't quote because I didn't think it was necessary but that may have lead to some confusion here.  You just happened to post in the intervening time.

I am very seriously questioning your attempt at using an entirely fanciful munition (8.25mm caseless, which you are trying to conflate to 8mm mauser) as a point of reference tho'.  There is no real world analog to that munition and we do not have adequate data to infer anything.

[Trekkin]

I am very seriously questioning your attempt at using an entirely fanciful munition (8.25mm caseless, which you are trying to conflate to 8mm mauser) as a point of reference tho'.  There is no real world analog to that munition and we do not have adequate data to infer anything.

Well, I think we can take a different approach using Dark Heresy, which gives us real-world numbers to work from in the form of ranges and the mass of autogun bullets -- which, in turn, lets us put an upper bound on the muzzle energy of the Agipinaa Type-II pattern Autogun, explicitly described as being equivalent to a lasgun. One bullet is ten grams, so there's no way for the muzzle energy to exceed 0.5 * 0.01 kg * ( 825 m/s )^2 = 3403 J. If we assume that equivalent "stopping power" and an identical damage rating at almost the same range means about the same amount of muzzle energy, that gives us an upper bound on lasgun power output.

[NullForceOmega]

Okay, that's a reasonable statement, I'm pretty certain Dark Heresy didn't exist prior to 2008 however, and google agrees with me, so there is no possible way that I could have taken that into account in 2000.

While that definitely improves the lethality of the lasgun to much more reasonable levels it still falls pretty firmly in the realm of modern weaponry (tho' definitely moving it into high-power munitions category).

[GiglameshDespair]

8mm mauser is a cartridge gig.  You cannot compare a cartridge to a caseless, they have radically different mechanisms, we therefore have no basis of comparison beyond extremely broad strokes.

And there have been multiple descriptions of the Vanquisher, in fluff and crunch, that straight up call it a 120mm smoothbore which uses APSD.  So to my purposes that would be a damned good base point to work from, the rules of aerodynamics and gravity don't change based on size, the same factors are at play whether it's a cannon round or a shotgun shell, and knowing the factors that define those things lets you easily back build what certain things mean from a mechanical standpoint.  Knowing the energy output of a weapon as compared to another weapon will then easily allow you to form a comparison.  So what If I had to determine footpounds of force then convert to joules and then compare based on other weapons within the setting to come to a conclusion, that's why it took twenty pages.

All of which is definitely overthinking such a ridiculous kitchen sink setting as 40K, but again, I was seventeen and had entirely too much time and nowhere near enough intellectual stimulation.

Sure you can; fundamentally they operate on the same principles of a bang propels a bullet out a barrel at a velocity. A gas-operated action is a gas-operated action whether it's caseless or cartridge, the main difference being whether it ejects a shell casing or not.
We can measure the energy of a round. For example, the G11's 4.7mm caseless was approx 1,044 ft⋅lbf, while a modern 5.56mm NATO round is typically around 1,328 ft⋅lbf.

Once again though, that's not really what I'm disputing.

If there's plenty of descriptions calling it a 120mm smoothbore using APSD, link to some if you would kindly. I've seen things calling it smoothbore, but nothing saying the actual calibre of it. It's fair to say a 40k round is probably more powerful than a modern round due to future chemistry, but even ignoring that, aspects such as barrel length and that there are apparently different types of Vanquisher cannon...

There's still the logical leap of energy output of a tank cannon compared to a laser. Where is the common ground? There's no statement I've ever seen telling the actual energy output of a lasgun, only that's it's similar to autoguns, which are clearly stronger than a .22lr.

[NullForceOmega]

No.  A 40k round is clearly NOT more powerful than modern rounds.  The comparison above where Trekkin kindly provided an actual measurement tells us absolutely that whatever the Empire uses it is in no way markedly better than modern propellants.  All you need to do is go to wiki and look at a list of modern calibers and then use a foot-pounds to joules calculator to see than numerous modern rounds are in fact more powerful than the supposed power of the 8.25 caseless Autogun. Though those rounds are less widespread than the overly common 5.56 NATO.

I don't have the title of the one reference I can most clearly recall regarding the Vanquisher being a 120mm, but I do remember the plot, an IG tank regiment is partnered with a Mechanicus unit to recover Commisar Yarrik's personal tank on a world overrun by orks, the guards suffer massive casualties (obviously) but the most relevant point is that one of the tanks (I am almost certain it was the commander's) was equipped with a Vanquisher and it was clearly described as being a 120mm smoothbore cannon firing APSD.  If I remembered that one's title I'd give it to you right now, because I very clearly recall that point.  There are others but that is the one that I remember right now.  Edit: Just checked the novel in question appears to be Gunheads, from 2009.  And to be honest, I don't think the Vanquisher was actually one of my primary points of reference, so I don't know why I was fixating on it, I've got one of the pages here and I've got numbers for the shotgun on it, and the heavy stubber down at the bottom.  Edit 2:  Other pages aren't in this box, gonna have to dig out one of the others.

And if we know the approximate energy output of several weapons (via their 'power' statistic) we can come to a fairly consistent estimate of how powerful a specific weapon that we don't have an absolute basis for (like a lasrifle) actually is.  Now, based on Trekkin's above estimate my old estimate is now clearly out of date, but the method used to arrive at it is still fully functional.

[Trekkin]

Okay, that's a reasonable statement, I'm pretty certain Dark Heresy didn't exist prior to 2008 however, and google agrees with me, so there is no possible way that I could have taken that into account in 2000.

While that definitely improves the lethality of the lasgun to much more reasonable levels it still falls pretty firmly in the realm of modern weaponry (tho' definitely moving it into high-power munitions category).

Oh, certainly. I wasn't meaning to imply that you should have, only that we have more ways to answer the question now -- and, as it happens, that answer comes out to a per-shot aperture energy somewhere around a 0.500 Magnum cartridge. Actual power consumption would be  higher depending on the efficiency (which I'm working out now) , but the laser loses energy with distance differently so the energy on target is not going to be equivalent.

That's partly because the terminal ballistics are so very different. You can't drill through soft tissue with a continuous beam, because the ejected plasma acts to diffuse it; you need arbitrarily short pulses, probably around a hundred of them to drill deeply enough, separated by a few microseconds to allow the plasma to disperse, giving a total shot time of milliseconds. This also changes the shape of the temporary wound cavity.

So yes, the lasgun is like a high-power round in terms of raw energy, but it's like dispersing the gunpowder from that round into a line of a hundred little firecrackers all set off in sequence in the target.

EDIT: I agree with you about the rounds not being more powerful, though. From the muzzle velocity it looks like, if 40k autoguns do use more powerful propellants, they also use less of them, which would make sense given that the human shoulder hasn't evolved to handle more recoil in the intervening millennia.

[ArchAIngel]

EDIT: Also, Battlefleet Gothic: Armada II beta tommorow, apparently. I am hype.

Yo WHAT


I don't care about one grot thinks about his obviously silly calcs, but THIS?


Give me a source please, this is important!