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Post by bigbombr on Aug 2, 2017 15:24:47 GMT
So wait, does the game actually respect projectile length vs penetration depth? Is firing needles instead of coins actually better at penetrating? Even more than that, does it respect overmatching of armor? (Though I doubt the coins a lot of people's guns are firing can really overmatch any angled armor IRL) As far as I can tell, yes to all your questions. At high mass or extreme velocities, the game appears to be a bit wonky though (reflecting a 5 t rubber slug without armour damage for example).
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Post by omnipotentvoid on Aug 2, 2017 16:20:26 GMT
So wait, does the game actually respect projectile length vs penetration depth? Is firing needles instead of coins actually better at penetrating? Even more than that, does it respect overmatching of armor? (Though I doubt the coins a lot of people's guns are firing can really overmatch any angled armor IRL) Overmatching depends on impulse, respective to impact area. Basically, to deflect a round an impulse must be imparted into it. The same impulse is imparted to the armor. If the armor can't withstand it (for example, because there isn't enough armor mass to absorb the impulse without it traveling at hundreds of meters per second) it will simply fail to reflect the round. The impulse is dependant on mass and velocity. Since modern guns are usually limited between a few hundred m/s to about 2km/s, the only way to achieve significantly better overmatching is to increase mass, thus size and thus caliber of weapons. But if you get a coin to be fast enough, it will overmatch the frontal plate of a challenger 2 MBT.
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Post by linkxsc on Aug 2, 2017 19:05:45 GMT
So wait, does the game actually respect projectile length vs penetration depth? Is firing needles instead of coins actually better at penetrating? Even more than that, does it respect overmatching of armor? (Though I doubt the coins a lot of people's guns are firing can really overmatch any angled armor IRL) Overmatching depends on impulse, respective to impact area. Basically, to deflect a round an impulse must be imparted into it. The same impulse is imparted to the armor. If the armor can't withstand it (for example, because there isn't enough armor mass to absorb the impulse without it traveling at hundreds of meters per second) it will simply fail to reflect the round. The impulse is dependant on mass and velocity. Since modern guns are usually limited between a few hundred m/s to about 2km/s, the only way to achieve significantly better overmatching is to increase mass, thus size and thus caliber of weapons. But if you get a coin to be fast enough, it will overmatch the frontal plate of a challenger 2 MBT. But overmatching is a geometric interaction between the diameter of a shell/shot and the thickness of an armored plate it's striking. And basically it says that a shot with diameter (basically length perpendicular to it's direction of travel) sufficiently larger than the raw thickness of the plate it's striking, offsets the benefits of angling that plate for greater effective thickness. Projectile speed doesn't matter with regards to overmatching. Also on the "getting a coin fast enough" You'll have to get a coin a fuck of a lot faster than you would a BB of the same thickness, as the coin interacts with a larger amount of armor, in spite of its greater mass. There's a reason why APCR, APDS, and APFSDS are vastly more effective against flat perpendicular plates, but will bounce against angled plates. Meanwhile, full caliber AP rounds might have precious little trouble getting through, despite them having lower "raw" penetration numbers, against a vertical plate.
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Post by omnipotentvoid on Aug 2, 2017 20:48:31 GMT
Overmatching depends on impulse, respective to impact area. Basically, to deflect a round an impulse must be imparted into it. The same impulse is imparted to the armor. If the armor can't withstand it (for example, because there isn't enough armor mass to absorb the impulse without it traveling at hundreds of meters per second) it will simply fail to reflect the round. The impulse is dependant on mass and velocity. Since modern guns are usually limited between a few hundred m/s to about 2km/s, the only way to achieve significantly better overmatching is to increase mass, thus size and thus caliber of weapons. But if you get a coin to be fast enough, it will overmatch the frontal plate of a challenger 2 MBT. But overmatching is a geometric interaction between the diameter of a shell/shot and the thickness of an armored plate it's striking. And basically it says that a shot with diameter (basically length perpendicular to it's direction of travel) sufficiently larger than the raw thickness of the plate it's striking, offsets the benefits of angling that plate for greater effective thickness. Projectile speed doesn't matter with regards to overmatching. Also on the "getting a coin fast enough" You'll have to get a coin a fuck of a lot faster than you would a BB of the same thickness, as the coin interacts with a larger amount of armor, in spite of its greater mass. There's a reason why APCR, APDS, and APFSDS are vastly more effective against flat perpendicular plates, but will bounce against angled plates. Meanwhile, full caliber AP rounds might have precious little trouble getting through, despite them having lower "raw" penetration numbers, against a vertical plate. Looking at it from a physical perspective, overmatching looks to see if the armor can withstand the round bouncing off the armor. This is primarily a question of impulse and its transfer, or more specifically for the case of overmatching a it is a matter of mass, velocity and contact area. Since velocity in modern shells varies by at most ~3km/s and most modern armor piercing shells are within about 1km/s of eachother (meaning any other shell is no more than about twice as fast as any regarded shell), mass and contact area become the deciding factors as these can vary by factors of hundreds depending on shell material, size and geometry. Since the shape and material of any given shell type (say APCBC vs APFSDS) are relatively the same across all shells of that type, caliber becomes decicive. This logic only extends to the velocities of modern projectiles, because the force aplied to the armor is small enough and the speed of impact slow enough, that the armor can withstand initial impact and spread the impulse imparted to the surounding armor. As such, overmatching is achieved when the armor can not spread the impact force fast enough to continue absorbing the impulse of projectile in order to redirect it. To put it simply, overmatch is achieved when the it is easier for the projectile to pass through the armor, than to be redirected by it. The most obvious point where the idea of overmatching not being based on velocity breaks down is the point when the projectile travels faster than the speed of sound in the armor. At this point, the armor is, by definition of the speed of sound in a material, no longer capable of spreading out the force of the impact fast enough to stop the projectile. However I'm fairly sure that the point where overmatching becomes mainly a point of velocity is before that. Not that it realy matters, because most projectiles used in CoaDE far exceed the velocity of sound in any material that has ever been theorized about, let alone observed, by humanity. At an impact velocity in the hundreds of km/s, even tungsten carbide will act more like a liquid than anything else.
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Post by Rocket Witch on Aug 2, 2017 23:33:55 GMT
DU has the benefits of being self-sharpening and when it hits 02 it can catch fire Basically any metal explodes into fiery death when its unpassivated surface (or liquid form) comes into contact with oxygen. So wait, does the game actually respect projectile length vs penetration depth? Is firing needles instead of coins actually better at penetrating? Even more than that, does it respect overmatching of armor? (Though I doubt the coins a lot of people's guns are firing can really overmatch any angled armor IRL) In the pre-release blog post on armour, qswitched has an image of various armour penetration effects with the statement that most of them are modelled by CDE. From this it can be reasonably assumed that there is a lot more detail than the ingame UI can show. In any case, questions like this demonstrate why the suggestions for a firing range come up so often. Is overmatch actually a thing outside of World of Tanks? It would vary a lot based on the armour composition to the extent that I can't entirely see a metric being made for it.
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Post by linkxsc on Aug 2, 2017 23:55:00 GMT
>Not that it realy matters, because most projectiles used in CoaDE far exceed the velocity of sound in any material that has ever been theorized about, let alone observed, by humanity.
Apparently conventional cannons don't exist. Might as well remove them then, clearly a waste of gamedev's time adding them in the first place. Sorry to have wasted time wondering why large caliber conventional cannon shots don't respond in a realistic manner when striking anything angled, and if systems were actually in place to operate on sub-speed of sound impacts. Apparently, you can do anything with ~5cm of aluminum @ ~30 degrees. Military's been doing it all wrong with these composites. Course ignoring any angular stuff, direct perpendicular penetration seems odd with large caliber/mass projectiles, though apparently spalling works and solid shot seems to break apart inside the target sometimes.
I fully realize that overmatching doesn't matter once you're beyond the speed of sound in the target material. It's right there in newton's impact depth approximation (which overmatching is just applying the concept to a 2d system instead of a 1d). That doesn't change the fact that the game does have sub material speed of sound impacts happening, and they seem a tad "off" to me.
>Is overmatch actually a thing outside of World of Tanks?
It existed in real life enough for militaries to consciously consider it when selecting guns and armor schemes in the post war. It's not something that wargaming made up out of their ass for a videogame mechanic if thats what you're asking. You can find plenty of info about it from long before WOT was even a thought. Course as it and War Thunder are the 2 games in the world that the concept are most relevant to, there tend to be a lot of discussion about them with relation to those games.
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Post by Rocket Witch on Aug 3, 2017 0:06:32 GMT
>Is overmatch actually a thing outside of World of Tanks? It existed in real life enough for militaries to consciously consider it when selecting guns and armor schemes in the post war. Ah, sorry, I didn't see the second page on this thread before now.
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Post by Enderminion on Aug 3, 2017 0:07:05 GMT
Is overmatch actually a thing outside of World of Tanks? It would vary a lot based on the armour composition to the extent that I can't entirely see a metric being made for it. yes, War Thunder has it
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Post by AdmiralObvious on Aug 3, 2017 1:14:38 GMT
The overmatch you see in other games is incredibly dumbed down. In WoT if the caliber is 3X the armor, it always penetrates, including APCR, which is basically half the caliber, but who cares, gold ammo pens everything.
War Thunder is a bit more sensible in that you need caliber 10X plate being hit, but still doesn't actually simulate what overmatching should be.
I think it would have to do with the masses of the armor involved, including composites which really mess with any type of equation you'd want to work with. Basically if the shot is so heavy, it won't care what the armor is made of if it's hitting a thin enough surface.
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Post by Enderminion on Aug 3, 2017 1:24:31 GMT
The overmatch you see in other games is incredibly dumbed down. In WoT if the caliber is 3X the armor, it always penetrates, including APCR, which is basically half the caliber, but who cares, gold ammo pens everything. War Thunder is a bit more sensible in that you need caliber 10X plate being hit, but still doesn't actually simulate what overmatching should be. I think it would have to do with the masses of the armor involved, including composites which really mess with any type of equation you'd want to work with. Basically if the shot is so heavy, it won't care what the armor is made of if it's hitting a thin enough surface. case in point: Graphene, right?
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Post by AdmiralObvious on Aug 3, 2017 2:07:03 GMT
case in point: Graphene, right? Pretty much, yes.
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