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Made in us
Consigned to the Grim Darkness





USA

Pyriel- wrote:I'd say no.
Concrete is heat resistant
Not as much as people think...

The people in the past who convinced themselves to do unspeakable things were no less human than you or I. They made their decisions; the only thing that prevents history from repeating itself is making different ones.
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But what about plascrete?
   
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Fresh-Faced New User




Dallas, TX

Lynata wrote:"Seems like a slightly more realistic/scientific explanation to the effect as described in the Wargear book.


How lasers work:

"Laser weapons usually generate brief high-energy pulses. A one megajoule laser pulse delivers roughly the same energy as 200 grams of high explosive, and has the same basic effect on a target. The primary damage mechanism is mechanical shear, caused by reaction when the surface of the target is explosively evaporated."

http://en.wikipedia.org/wiki/Directed-energy_weapon

=/=

0110111101 
   
Made in se
Longtime Dakkanaut





Gothenburg

Not as much as people think...

But enough to not allow a small hand held pulse of light to burn through a significal amount of it.

There are also big differences in types of concrete and their energy resistance.

The whole question woudl be pretty simple if we were to know the rough energy output of one lasgun shot.
We don't know that but it can nevertheless be guessed by using an average of canon fluff damage examples and recalculating the required energy requirements.
I´m pretty sure a lasgun has the equivalent damage output on biological targets as a modern day rifle (autogun).
If this is the case there is no way it can burn through concrete with ease since kinetic energy and heat are treated quite different by different materials like concrete.


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USA

Pyriel- wrote:
Not as much as people think...

But enough to not allow a small hand held pulse of light to burn through a significal amount of it.
... a small hand held weapon which gives off a pulse of energy which IIRC was 14 megajoules (~2.8kg of explosives equivalent), more than enough to cause damage to anything it hits that isn't specifically designed to resist such rapid absorption of energy.

This message was edited 1 time. Last update was at 2011/10/04 15:27:23


The people in the past who convinced themselves to do unspeakable things were no less human than you or I. They made their decisions; the only thing that prevents history from repeating itself is making different ones.
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Made in gb
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Medway

3Kgs of explosive (that produces 14MJ) won't punch through 2m of concrete unless the charge is shaped specifically to achieve this.

Explosions are powerful but unless that power is focussed they aren't that destructive.

The common example is this:
hold a banger on the flat palm of your hand and when it goes off you won't be hurt.
If you clench the banger in a tight fist it will blow your fingers off.

A blast with no shrapnel is oddly benign, a soldier 10m from a grenade blast only has a 20% chance of being wounded.

The lasgun in this case produces a blast caused by vaporising/subliming material. That blast is unfocussed and would produce a semi-lenticular crater.

For it to penetrate it would need to create a deep wound channel, a focussed blast but it can't do that because the vapour from the initial impact would prevent the light from a longer pulse from reaching the target.

I don't see it.


That said, the guys who write the fluff do not necessarily have any experience with lasers or explosives (who has).

This message was edited 1 time. Last update was at 2011/10/04 18:59:09


Ginge 
   
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Noctis Labyrinthus

Melissia wrote:... a small hand held weapon which gives off a pulse of energy which IIRC was 14 megajoules (~2.8kg of explosives equivalent), more than enough to cause damage to anything it hits that isn't specifically designed to resist such rapid absorption of energy.


As far as I know, the amount of energy in "joules" has never been stated.

But, LAsguns are said to operate in the 19 megathule range.

There is no real life unit of measurement called a "thule," it's a meaningless term.
   
Made in us
Gore-Soaked Lunatic Witchhunter




Seattle

Let's repeat this again, for those who missed it at home:

There is no canon in 40k. It's all canon, and none of it is. This means that you're allowed to pick and choose what you want from the setting and run with it. If you want lasguns to shoot through 2 meters of concrete, 2 centimeters of concrete, or unable to pierce a damp sack... you can. In the setting itself, lasguns work at the 19 megathule range... according to the Infantryman's Uplifting Primer and other sources... but what the holy feck is a thule? And how do you get a million of them? We don't know, we can't know, and so any findings based on this data is meaningless.

It is best to be a pessimist. You are usually right and, when you're wrong, you're pleasantly surprised. 
   
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USA

rob-or-ross wrote:Explosions are powerful but unless that power is focussed
You mean focused like... a lasgun would do? Because said energy is focused on a specific, relatively small location due to it superheating said location.


Automatically Appended Next Post:
Void__Dragon wrote:But, LAsguns are said to operate in the 19 megathule range.

There is no real life unit of measurement called a "thule," it's a meaningless term.
Let's take that as a corruption of the term Joule then. 19 megajoules of heat being instantly and efficiently transferred into a target would have a disastrous effect on it..

This message was edited 1 time. Last update was at 2011/10/04 19:50:04


The people in the past who convinced themselves to do unspeakable things were no less human than you or I. They made their decisions; the only thing that prevents history from repeating itself is making different ones.
-- Adam Serwer
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Seattle

But a thule, in terms of power rating, is equivalent to a pico-joule. So, really, 19 megathules is the necessary level of power to toast bread thoroughly or cause a pretty gnarly sunburn on a human-equivalent target.

...

We can't just make up real-world comparisons to 40K terms. We have no idea what a "megathule" is, or what it's supposed to represent, other than that it's an impressive amount of energy output (based on the text of the Uplifting Primer... take that with a grain of salt, of course). We have no real-world comparison, as we have no real-world, man-portable lasers capable of firing a short burst of lethal light.

It is best to be a pessimist. You are usually right and, when you're wrong, you're pleasantly surprised. 
   
Made in nz
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Auckland, New Zealand

The answer to the topic creator is no, the lasgun will not shoot through 2 metres of concrete. The lascannon might have problems with one shot (multiple shots obviously would go through). The main battery from a Space Marine barge? You'd be hard pressed to find the building the concrete was attached to after firing.

Molten aluminium, dripped onto concrete, will cause small pock-marking explosions.


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Medway

Tenacious.

I like you.


The beam of light is (sort of) focussed, something focussed will (strictly speaking) eventually become a point.
A laser will not since its photons run parallel.

It is conceivable that in the distant future the Lasgun has an automatic range finder in it that focusses the beam so that it becomes a point at the point where it hits the enemy.
This might be another problem of the people who write the fluff not realising that the defining characteristic of a laser is that it is not focussed.

Once that (arguably) focussed beam of light hits a target it ceases to exist, it exchanges its cohesive nature for a super heated ball of plasma that causes a blast, that blast is not focussed.

You need to use a special type of explosive charge to create that effect.

If the Lasgun was using some as-yet undiscovered technology in conjunction with the laser to influence the blast and give it the same functionality as a shaped charge (like a diverted energy function nuke from Peter F Hamilton's excellent sci fi) it would be the most powerful anti-armour weapon in the whole game.

I like the Lasgun (I prefer 70 of them firing at one target).

I like the Guard.

I don't see 2 to 3 meters of concrete.


On the Joule/Thule thing:

I would be inclined to take the Thule to be a Joule for two reasons.

1. The Joule is an SI derived unit which means it is only one separation away from physical constants, it or its equivalent will exist as long as there is technology.

2. The same fluff authors who's limited understanding of science leads to the above arguments are also prone to the same vanity as a lot of sci-fi/fantasy novelists.
Namely, using nouns in common usage is not "future-y" enough for them and they pointlessly make up new ones.


Ginge 
   
Made in us
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I think most of you are forgetting one thing:

Lasguns are carried by Imperial Infantry. When was the last time you saw just one infrantry man shooting at a target? Thought so.

Therefore, yes, an Imperial lasgun can blow right through a 3M concrete wall... Because it will never be just one gun. It's going to be at least 100 of them shooting the same wall and when the firing is over the wall will simply not be there anymore.



------------------
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Seattle

Here's the thing about cover and weapons:

If cover, let's say a wall of sandbags, can stop bullets from 1 assault rifle, it can stop bullets from 1000 assault rifles.

Eighteen inches of packed earth can stop 5.56mm rounds indefinitely. Doesn't matter how many M16s you shoot at that wall of packed earth, it's never going to go away.

If we extrapolate that lasguns work on the same principle, we get the same results. If one lasgun cannot shoot through a concrete wall, then 1000 of them aren't going to do it, either. Cover simply doesn't work that way... at least, not until you're dealing with weapons actually piercing it. When you have cover being carried away/blown away by the rounds hitting it, then you can wear it away with massed fire. If not? Then it will never happen.

It is best to be a pessimist. You are usually right and, when you're wrong, you're pleasantly surprised. 
   
Made in rs
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Holy Terra

Psienesis wrote:Here's the thing about cover and weapons:

If cover, let's say a wall of sandbags, can stop bullets from 1 assault rifle, it can stop bullets from 1000 assault rifles.

Eighteen inches of packed earth can stop 5.56mm rounds indefinitely. Doesn't matter how many M16s you shoot at that wall of packed earth, it's never going to go away.

If we extrapolate that lasguns work on the same principle, we get the same results. If one lasgun cannot shoot through a concrete wall, then 1000 of them aren't going to do it, either. Cover simply doesn't work that way... at least, not until you're dealing with weapons actually piercing it. When you have cover being carried away/blown away by the rounds hitting it, then you can wear it away with massed fire. If not? Then it will never happen.


I would like to see sandbag wall survive 30.000 bullets from 1000 assault riffles
especially when the ammo is this:
Spoiler:


And Lasgun is not ordinary rifle, it's a rifle firing focused laser beam that focus energy on impact. That;s pretty much more powerful then any assault rifle today.

This message was edited 2 times. Last update was at 2011/10/04 22:02:37


For Emperor and Imperium!!!!
None shall stand against the Crusade of the Righteous!!!
Kanluwen wrote: "I like the Tau. I just don't like people misconstruing things to say that it means that they're somehow a huge galactic threat. They're not. They're a threat to the Imperium of Man like sharks are a threat to the US Army."
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Viersche wrote:
Abadabadoobaddon wrote:
the Emperor might be the greatest psyker that ever lived, but he doesn't have the specialized training that a Grey Knight has. Also he doesn't have a Grey Knight's unshakable faith in the Emperor.


The Emperor doesn't have a GKs unshakable faith in the Emperor which is....basically himself?

Ronin wrote:

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'focussed laser beam'. You realise that's an oxymoron, right?

Arguing with some people is like playing chess with a pigeon. You can play the best chess in the world, but at the end of the day the pigeon will still knock all the pieces off the board and then gak all over it. 
   
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Longtime Dakkanaut





Gothenburg

... a small hand held weapon which gives off a pulse of energy which IIRC was 14 megajoules (~2.8kg of explosives equivalent), more than enough to cause damage to anything it hits that isn't specifically designed to resist such rapid absorption of energy.

Canon source on this please!

There is no way a common "flashlight" rifle will produce the energy equivalent of 3kg explosive and still be widely considered just that, a "flashlight".
You cant eat your cake and still have it.

A common shot from a lasgun would that way turn a person it hits into wet paste. Kind of like the grey knights did to the sisters of battle in order to remain uncorrupted by the blood tide. Sister anti deamon paste
lol


3Kgs of explosive (that produces 14MJ) won't punch through 2m of concrete unless the charge is shaped specifically to achieve this.

Explosions are powerful but unless that power is focussed they aren't that destructive.

This!

The common example is this:
hold a banger on the flat palm of your hand and when it goes off you won't be hurt.
If you clench the banger in a tight fist it will blow your fingers off.

More to it then this.
If a lasgun shot produces 14Mj of power and hits a concrete wall it will at most crumble and at least produce spall. There wont be a tight "beam" slicing clean thorough.
Also, if you hold 3kg explosives in your open palm the forensics will use a toothbrush to scrap your residue of the floor since your body will be hit by a wall of compressed air traveling at 6 km per second, if you hold it in a clenched fist the exact same result will be produced.
Gakking ridiculous to even claim such energy levels or if they were found in imperial armour I can understand it since it is written by the same clueless idiots who thought landraider armour is the equivalent to that of a WW2 sherman.

That said, the guys who write the fluff do not necessarily have any experience with lasers or explosives (who has).

Or tank armour for that matter

But, LAsguns are said to operate in the 19 megathule range.

There is no real life unit of measurement called a "thule," it's a meaningless term.

Assuming those are joules would be wrong as those are insane amounts of energy for a little lasgun blast. Another good example of GW fluff writers and common sense/logic.
19Mj is enough to turn a human into instant BBQ.

We can't just make up real-world comparisons to 40K terms. We have no idea what a "megathule" is, or what it's supposed to represent, other than that it's an impressive amount of energy output (based on the text of the Uplifting Primer... take that with a grain of salt, of course). We have no real-world comparison, as we have no real-world, man-portable lasers capable of firing a short burst of lethal light.

We can do it the easy way, let us agree on something at least, that a lasgun is somewhat as powerful as a rifle, say an 7.62 round. This assumption is based on the common usage of a lasgun vs an autogun, both are used to take out and/or wound human sized targets (in the kJ range) and not flashboil a meganob with one shot (MJ range).
Lets assume the lasgun delivers roughly as much thermal energy to the target as a modern day 7.62 round does, we will end up with roughly 1.5-2 kilo joules worth of energy.

This is fully adequate to kill or heavily wound a human, flak armour or not and this IS the primary role of a lasgun.

Now go read up on how much energy it takes to cause spall or crumbling in concrete and calculate how much a lasgun shot would do to said material (not much at all).

Even if you somehow can superhotshot a whole lasgun magazine, all 30 or 60 shots into one super powerful blast you'll end up with 60 to 120 kJ worth of energy, far below even one mega joule and besides the hotshot ammo in fluff uses up "only" twice the amount of energy, not the whole magazine.
Well if we take the sniperlas from Gaunts Ghosts then it has roughly 60KJ one-shot magazines true but still not enough to penetrate large quantities of concrete.

So solved it for you, now by logic you know how much energy is in a lasgun shot and you can now calculate exactly what it can or cant destroy.

If the Lasgun was using some as-yet undiscovered technology in conjunction with the laser to influence the blast and give it the same functionality as a shaped charge (like a diverted energy function nuke from Peter F Hamilton's excellent sci fi) it would be the most powerful anti-armour weapon in the whole game.

Hehe, quantum busters ftw!

I think most of you are forgetting one thing:

Lasguns are carried by Imperial Infantry. When was the last time you saw just one infrantry man shooting at a target? Thought so.

Therefore, yes, an Imperial lasgun can blow right through a 3M concrete wall... Because it will never be just one gun. It's going to be at least 100 of them shooting the same wall and when the firing is over the wall will simply not be there anymore.

Using your logic or rather lack of, we dont need tanks in todays armies since everybody knows a modern soldier doesnt fire alone, there are platoons of them and all can fire at the same target, be it a wall, house, enemy tanks etc and even the toughest of tanks will all be blown to pieces just as long as enough soldiers fire at them...*sigh*

Christ on a pushbike!

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Brother Coa wrote:
KamikazeCanuck wrote:I think a lasgun isn't much more powerful than an AK-47.


What?
Dude in all do respect....
Lasgun tear off limbs with it's mini plasma explosion.
AK-47 just make small whole in you.



Dude, a lasgun tears off limbs about as often as an AK-47 does. It's not like in the movies, bullets do terrible things to people. In Gaunt's Ghosts a trooper gets hit in the shoulder and it explodes and must be replaced but his arm remains intact.
An M16 would still be S3 AP- in the grim darkness of the far future.


Automatically Appended Next Post:
Joules aren't Thules. Thules are Thules!

This message was edited 1 time. Last update was at 2011/10/04 22:28:24


 
   
Made in rs
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Holy Terra

KamikazeCanuck wrote:
Dude, a lasgun tears off limbs about as often as an AK-47 does. It's not like in the movies, bullets do terrible things to people. In Gaunt's Ghosts a trooper gets hit in the shoulder and it explodes and must be replaced but his arm remains intact.
An M16 would still be S3 AP- in the grim darkness of the far future.


AK-47 never does that, that's M-16 ( her bullet is desing to get into you and rip you apart inside. 7.62x39mm ammo just go trough you from one side to the other ) and that's rare cases only. Codex say that Lasgun shot can blow up limbs on unarmored Human, and we all know that only BUM-BUM bullets today can do that.

For Emperor and Imperium!!!!
None shall stand against the Crusade of the Righteous!!!
Kanluwen wrote: "I like the Tau. I just don't like people misconstruing things to say that it means that they're somehow a huge galactic threat. They're not. They're a threat to the Imperium of Man like sharks are a threat to the US Army."
"Pain is temporary, honor is forever"
Emperor of Mankind:
"The day I have a sit-down with a pansy elf, magic mushroom, or commie frog is the day I put a bolt shell in my head."
in your name it shall be done"
My YouTube channel: http://www.youtube.com/user/2SSSR2

Viersche wrote:
Abadabadoobaddon wrote:
the Emperor might be the greatest psyker that ever lived, but he doesn't have the specialized training that a Grey Knight has. Also he doesn't have a Grey Knight's unshakable faith in the Emperor.


The Emperor doesn't have a GKs unshakable faith in the Emperor which is....basically himself?

Ronin wrote:

"Brother Coa (and the OP Tadashi) is like, the biggest IoM fanboy I can think of here. It's like he IS from the Imperium, sent back in time and across dimensions."

 
   
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You'd be surprised what you can do if you hit the right place...

Arguing with some people is like playing chess with a pigeon. You can play the best chess in the world, but at the end of the day the pigeon will still knock all the pieces off the board and then gak all over it. 
   
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Seattle

I would like to see sandbag wall survive 30.000 bullets from 1000 assault riffles


Go ask any soldier who has any experience, at all, with building infantry fortifications.

There's a reason we fill sandbags in a desert or a jungle, you see. They stop bullets. All night and day long. The difference being that sandbags, because the bag itself gets damaged, have to be replaced. If I had a wall of the same dimensions as a fox-hole's forward wall of packed earth? It would stop bullets forever.

So replace said sandbag wall with an earthen berm, like the kinds they put behind outdoor firing ranges. You know what they don't do at outdoor firing ranges? Worry much about replacing the berm after a busy day of business. Packed earth stops small-arms fire indefinitely. It, basically, eats bullets. Just takes them right in and stops them cold, even adding their mass to its own. The only thing you need to concern yourself with now is erosion of said earthen berm by rain and wind, a totally different concept than the point-impact of an assault rifle round, whether that's a 5.56mm, a 7.62mm, a 7mm, an 8mm or any other small-arm caliber you care to suggest.


AK-47 never does that, that's M-16 ( her bullet is desing to get into you and rip you apart inside. 7.62x39mm ammo just go trough you from one side to the other ) and that's rare cases only. Codex say that Lasgun shot can blow up limbs on unarmored Human, and we all know that only BUM-BUM bullets today can do that.


Anyone who told you that the AK47 cannot and does not blow limbs off lied to you. Lied to you quite badly. The 5.56mm of the M16, with its built-in tumble effect is a highly lethal round... but it doesn't blow limbs off very easily, or well. Shoot someone in the arm with a '16, the round is liable to hit the bone, deflect, and go out the side. The slower, heavier 7.62mm round is far more likely to hit the bone, shatter it, and continue on through without so much as a by-your-leave and exit the limb at the opposite side. Of course, as it is tearing through muscle and sinew at the same time, the limb is likely to drop off, or at least be so heavily mangled that amputation may be required.

This message was edited 1 time. Last update was at 2011/10/04 22:42:44


It is best to be a pessimist. You are usually right and, when you're wrong, you're pleasantly surprised. 
   
Made in rs
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Holy Terra

Psienesis wrote:
Go ask any soldier who has any experience, at all, with building infantry fortifications.

There's a reason we fill sandbags in a desert or a jungle, you see. They stop bullets. All night and day long. The difference being that sandbags, because the bag itself gets damaged, have to be replaced. If I had a wall of the same dimensions as a fox-hole's forward wall of packed earth? It would stop bullets forever.

So replace said sandbag wall with an earthen berm, like the kinds they put behind outdoor firing ranges. You know what they don't do at outdoor firing ranges? Worry much about replacing the berm after a busy day of business. Packed earth stops small-arms fire indefinitely. It, basically, eats bullets. Just takes them right in and stops them cold, even adding their mass to its own. The only thing you need to concern yourself with now is erosion of said earthen berm by rain and wind, a totally different concept than the point-impact of an assault rifle round, whether that's a 5.56mm, a 7.62mm, a 7mm, an 8mm or any other small-arm caliber you care to suggest.


Like I said, after some quantity of bullets that "indestructible wall" start failing and wall start falling apart. Sandbags are tough, I admit that - buy you said that they cannot take much same punishment as normal wall can - and that is my point.


Anyone who told you that the AK47 cannot and does not blow limbs off lied to you. Lied to you quite badly. The 5.56mm of the M16, with its built-in tumble effect is a highly lethal round... but it doesn't blow limbs off very easily, or well. Shoot someone in the arm with a '16, the round is liable to hit the bone, deflect, and go out the side. The slower, heavier 7.62mm round is far more likely to hit the bone, shatter it, and continue on through without so much as a by-your-leave and exit the limb at the opposite side. Of course, as it is tearing through muscle and sinew at the same time, the limb is likely to drop off, or at least be so heavily mangled that amputation may be required.


Funny, people that have been in Croatia, Bosnia and Kosovo tell me a different thing. Some of them get wounded in arm several times and the arm is still in place, and they use it today like me or you. Only 1 guy lost an arm, normally he lost it because tank shell exploded near him. My point is that 1 bullet can't rip arm, several can - Lasgun can blow up limb in 1 shot.

Back to OP.... 14MJ of energy is a LOT. Still, all that energy is concentrated in one thing: exploding at the end of the beam ( mini plasma explosion ). So Lasgun can only make damage on the surface of the wall, not go trough it.


For Emperor and Imperium!!!!
None shall stand against the Crusade of the Righteous!!!
Kanluwen wrote: "I like the Tau. I just don't like people misconstruing things to say that it means that they're somehow a huge galactic threat. They're not. They're a threat to the Imperium of Man like sharks are a threat to the US Army."
"Pain is temporary, honor is forever"
Emperor of Mankind:
"The day I have a sit-down with a pansy elf, magic mushroom, or commie frog is the day I put a bolt shell in my head."
in your name it shall be done"
My YouTube channel: http://www.youtube.com/user/2SSSR2

Viersche wrote:
Abadabadoobaddon wrote:
the Emperor might be the greatest psyker that ever lived, but he doesn't have the specialized training that a Grey Knight has. Also he doesn't have a Grey Knight's unshakable faith in the Emperor.


The Emperor doesn't have a GKs unshakable faith in the Emperor which is....basically himself?

Ronin wrote:

"Brother Coa (and the OP Tadashi) is like, the biggest IoM fanboy I can think of here. It's like he IS from the Imperium, sent back in time and across dimensions."

 
   
Made in us
Consigned to the Grim Darkness





USA

Obviously the thule must be referring to this:



Because of this, I am assuming that the megathule refers to Thule in his dreadnought state. As I'm sure you'll admit, this indicates a megathule is quite a large amount of energy, and the lasgun fires nineteen of them!

The people in the past who convinced themselves to do unspeakable things were no less human than you or I. They made their decisions; the only thing that prevents history from repeating itself is making different ones.
-- Adam Serwer
My blog
 
   
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Crazed Zealot






Psienesis wrote:Here's the thing about cover and weapons:

If cover, let's say a wall of sandbags, can stop bullets from 1 assault rifle, it can stop bullets from 1000 assault rifles.

Eighteen inches of packed earth can stop 5.56mm rounds indefinitely. Doesn't matter how many M16s you shoot at that wall of packed earth, it's never going to go away.


Actually, no. First, in order for a material to resist an impact with no damage, their has to be a great disparity between the hardness, strength and density of the cover/armour and the projectile, such that the projectile is shattered, or the projectile must glance off and use up it's energy travelling elsewhere. Such is common to things like steel alloy armours, which are hard, dense and structurally consistent (if made correctly). Although even then, the complexities of armour penetration mechanics mean that results will vary. Concrete and packed earth (whether in or out of canvas/plastic bags) are rather porous and not particularly dense. They both tend to ablate away when hit by impacts. You can consult numerous USMC and US Army manuals (many free on the internet now) which give specifications on how many rounds of a given type is required to punch through a given building material, such instructions being quite valuable for machinegunners. A wall of packed earth being used for firing practice will not be hit by those rounds repeatedly at one fixed point in sufficient quantity to punch through. The rounds will tend to be dispersed along it's length, allowing it to retain sufficient structure to remain. However, assuming sufficient ammunition and continuous fire upon the same point, you could easily gouge a hole out of it.

For example, it requires an average of thirty-five 5.56mm NATO rounds at 100m to penetrate 8 inches of reinforced concrete, and around 220 of them to penetrate a double sandbag wall 24" thick at the same range.

This message was edited 3 times. Last update was at 2011/10/05 00:50:12


"In vocatione nostrum, rectitudo et peccatum non sunt. Praeteritum momenti usque momento praesens commutat. Solummodi precare posteritatem justificaturus actus vestros." 
   
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Melissia wrote:Obviously the thule must be referring to this:



Because of this, I am assuming that the megathule refers to Thule in his dreadnought state. As I'm sure you'll admit, this indicates a megathule is quite a large amount of energy, and the lasgun fires nineteen of them!


It's certainly a larger calibre than I thought...

 
   
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Gothenburg

Thule in his dreadnought state. As I'm sure you'll admit, this indicates a megathule is quite a large amount of energy, and the lasgun fires nineteen of them!

19 dreadnoughts will most certainly tear through a concrete wall

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You can consult numerous USMC and US Army manuals (many free on the internet now) which give specifications on how many rounds of a given type is required to punch through a given building material, such instructions being quite valuable for machinegunners


Yes, you can, as these are the sources that most of my knowledge in this area come from. Rather, the practical application of information from those sources, as I spent many years in the Army doing exactly this sort of thing. Believe me, no machinegunner is memorizing the FM on building materials and round-types needed to penetrate them. They don't carry half a dozen kinds of ammunition for a squad-automatic... at best, you've got 3. Standard ball, tracer, and maybe some AP. He's going to eyeball it, give it a burst and see what happens. If he sees daylight? He's going to keep shooting. If he doesn't? He's going to keep shooting to keep their heads down while the RTO calls for fire or the mortar team gets the tube set up.

This is why emplaced defenses, like sandbag walls, pillboxes, foxholes, etc, all tend to have a fairly consistent appearance. The science that goes into their construction is, after nearly a century of warfare involving automatic firearms and large armies, pretty well understood. The materials involved may change slightly (we were still using burlap sacks left over from the Vietnam War when I was in, though switched to plastic for a disaster-relief mission for an area affected by flooding, since plastic is waterproof, but a guy I know who is still in mentioned that there is talk of issuing woven-kevlar/kevlon sandbags in the future)... but the physics do not.

Sandbag emplacements have the added benefit of being far easier to produce than a wall of packed earth (not just a random pile of dirt that is a foot and a half across). Need 18 inches deep? That's 3 rows of sandbags deep, measured across their width. Stack. Rinse, repeat. Leave gaps in the corners of your wall, you're going to want something to shoot out of.

For example, it requires an average of thirty-five 5.56mm NATO rounds at 100m to penetrate 8 inches of reinforced concrete, and around 220 of them to penetrate a double sandbag wall 24" thick at the same range.


By "reinforced concrete" I assume they mean with rebar within poured block? For the physics of this, that's irrelevant reinforcement, and might, in fact, make the wall more brittle to incoming fire, given the way rebar and poured block work. That said... a 5.56mm round is most likely not going to leave a quarter-inch depression in the wall... especially if it runs into one of those reinforced rebar bits (if it doesn't, then the use of reinforcement in this context needs clarifying, as there are lots of ways to reinforce concrete!). It's a fast round, and highly lethal to soft targets, but, copper jacket or no, makes little difference to a concrete wall. The round hasn't got the mass to dig a quarter of an inch into the wall with every shot. This is also going to be highly dependent on the age of the concrete. The older it gets, the more its cured... and, after a certain age, it actually starts to get more brittle, which may permit a 5.56 round to do that. Upshot.... there's too many variables in this equation to take such a statement at face value. In addition to myself having served in the Army, my father was a concrete mason. I spent far too many summers working for him to not know a bit about the varieties and vagaries of concrete. There's dozens and dozens of different kinds of concrete... densities, mixtures, additives, etc... simply too many to say that "concrete" stops X number of Y kinds of bullets.

Having been on both the giving and receiving end of fire behind 24" of sandbags... it requires a whole hell of a lot more bullets than 220 to tear it apart... you could probably burn two or three belts from from a 60 and still have plenty of sandbags looking back at you. Sure, it's not going to be pretty after that, but it should still be functional... assuming you placed your bags properly, and didn't half-ass it like legos.

Of course, if they are projecting the force of one round on a sandbag and then determining the energy required to tear through them and from that determining the multiplicative results... well, that might be accurate, from a technical standpoint, but it's not something you will ever see in reality, since no one is going to be able to put 220 rounds dead on target on the exact same point of the sandbag wall. You know we stack a layer of sandbags six to eight deep on top of foxholes to defend from mortar fire, right? Works pretty good, too, provided the material supporting your overhead cover doesn't give away. Then you just get buried alive.

Sandbags, though, aren't packed earth. They're just bags of sand in a more-or-less confined place. Packed earth requires lots more time and effort (not to mention tools) to have on hand in most cases.

19 dreadnoughts will most certainly tear through a concrete wall


Word.

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CRASSUS ARMOURED ASSAULT TRANSPORT!

IIRC, a megathule is a thousand thules, (could be misremembering).

So take a thousand Davian Thules. BAM, that's a lasgun.

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 Atma01 wrote:

And that is why you hear people yelling FOR THE EMPEROR rather than FOR LOGICAL AND QUANTIFIABLE BASED DECISIONS FOR THE BETTERMENT OF THE MAJORITY!

 
   
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Noctis Labyrinthus

Elector wrote:IIRC, a megathule is a thousand thules, (could be misremembering).

So take a thousand Davian Thules. BAM, that's a lasgun.


"Mega" in terms of of units of measurement means "million."

So 19,000,000 Davian Thules apparently.
   
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California

Psienesis wrote:
In the setting itself, lasguns work at the 19 megathule range... according to the Infantryman's Uplifting Primer and other sources... but what the holy feck is a thule? And how do you get a million of them? We don't know, we can't know, and so any findings based on this data is meaningless.


Well, obviously a Thule is the average amount of manliness emitted by Davian Thule when he's at rest. That a Lasgun is 19 million times that is because a Davian Thule at rest is just a manly statue, while a Lasgun is a FREAKING LASER BEAM.

Thread degenerates into endless Thule jokes.

This message was edited 1 time. Last update was at 2011/10/05 05:54:05


Dirty Harry wrote:I know what you're thinking. "Did he fire six shots or only five?" Well, to tell you the truth, in all this excitement I kind of lost track myself. But being as this is a .44 Magnum, the most powerful handgun in the world, and would blow your head clean off, you've got to ask yourself one question: Do I feel lucky? Well, do ya, punk?
 
   
 
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