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Cybergod #1 Posted Nov 23 2012 - 20:52

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I was in General Chat last night dumbing my self down with every comment I read. Watching 4 players argue about how HEAT Rounds work with either of the 4 knowing how it works. SO here you guys go. Just a simple copy and paste. But at least it's the truth.


A type of chemical energy ammunition (i.e., ammunition where the penetrative power is generated by explosive energy rather than by kinetic energy) fitted with a high explosive anti-tank (HEAT) – or hollow charge – warhead. The HEAT warhead is not velocity dependent. In order to achieve penetration, the limited amount of explosive is shaped into an inverted, rearward-facing cone lined with a metal such as copper or some other ductile material. When the charge is detonated by a nose fuze, a jet of high energy gas and vaporised metal is projected forward at speeds, typically, of 6,000 m per second. This plasma jet acts like a cutting torch.
The detonation of the limited amount of high explosive contained within a shell fired from a tank gun is unlikely to do lethal damage to a tank and therefore a means must be found to focus the energy of the detonation into some form of high-energy jet. The most effective and widely used method is to shape the detonation wave so that the total energy available is directed onto a small cross-sectional area of the target. This is achieved by manufacturing the explosive charge into the shape of an inverted, rearward-facing cone and lining it with copper or some other low melting point, ductile metal. When the charge is detonated by the fuze mounted in the nose, a jet of high-energy gas and vaporised metal from the cone is projected axially forward (the Munroe effect). This jet, travelling at a speed of around 6,000 m per second, burns its way through the armour like a cutting torch. The effectiveness and penetration of the jet depends on the diameter of the cone and hence the calibre of the gun, the type of metal liner and the 'stand-off' distance from the target at which the charge is detonated.
The penetration of a HEAT round is severely degraded if the charge is spun, so the projectile must be fin-stabilised (even at 400 rpm penetration is reduced by about 25%). If the hollow charge is to be fired from a rifled barrel, then some means such as slipping driving bands must be used to limit, or preferably eliminate, the spin. Although a relatively small cone diameter can produce a very impressive depth of penetration (typically 5-6 times cone diameter), lethahty is low unless it over-matches the target by at least 33%. However, if an exit hole in excess of 24 mm in diameter is produced, the terminal effect inside the vehicle is likely to be considerable as the jet continues into the target with considerable residual energy bringing with it 'spall' or splinters torn off the armour plate. Thus, the performance and effect of the hollow charge round is largely dependent on cone diameter.



Myths of Heat rounds.

HEAT rounds do not depend in any way on thermal phenomena for their effectiveness. In particular, the shaped charge jets do not "melt their way" through armor, only reaching 500-600°C, and instead rely on extreme pressure to force a hole through the armor

Heat rounds do not penetrate then explode which I do have to say at one time I thought was the way they worked.

Zaratank #2 Posted Nov 23 2012 - 21:02

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View PostCybergod, on Nov 23 2012 - 20:52, said:

Heat rounds do not penetrate then explode which I do have to say at one time I thought was the way they worked.
Me too. Thanks for this bit of enlightening info.

SpyHawk9 #3 Posted Nov 23 2012 - 21:20

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View PostCybergod, on Nov 23 2012 - 20:52, said:

I was in General Chat last night dumbing my self down with every comment I read. Watching 4 players argue about how HEAT Rounds work with either of the 4 knowing how it work. SO here you guys go. Just a simple copy and paste. But at least it's the truth.


A type of chemical energy ammunition (i.e., ammunition where the penetrative power is generated by explosive energy rather than by kinetic energy) fitted with a high explosive anti-tank (HEAT) – or hollow charge – warhead. The HEAT warhead is not velocity dependent. In order to achieve penetration, the limited amount of explosive is shaped into an inverted, rearward-facing cone lined with a metal such as copper or some other ductile material. When the charge is detonated by a nose fuze, a jet of high energy gas and vaporised metal is projected forward at speeds, typically, of 6,000 m per second. This plasma jet acts like a cutting torch.
The detonation of the limited amount of high explosive contained within a shell fired from a tank gun is unlikely to do lethal damage to a tank and therefore a means must be found to focus the energy of the detonation into some form of high-energy jet. The most effective and widely used method is to shape the detonation wave so that the total energy available is directed onto a small cross-sectional area of the target. This is achieved by manufacturing the explosive charge into the shape of an inverted, rearward-facing cone and lining it with copper or some other low melting point, ductile metal. When the charge is detonated by the fuze mounted in the nose, a jet of high-energy gas and vaporised metal from the cone is projected axially forward (the Munroe effect). This jet, travelling at a speed of around 6,000 m per second, burns its way through the armour like a cutting torch. The effectiveness and penetration of the jet depends on the diameter of the cone and hence the calibre of the gun, the type of metal liner and the 'stand-off' distance from the target at which the charge is detonated.
The penetration of a HEAT round is severely degraded if the charge is spun, so the projectile must be fin-stabilised (even at 400 rpm penetration is reduced by about 25%). If the hollow charge is to be fired from a rifled barrel, then some means such as slipping driving bands must be used to limit, or preferably eliminate, the spin. Although a relatively small cone diameter can produce a very impressive depth of penetration (typically 5-6 times cone diameter), lethahty is low unless it over-matches the target by at least 33%. However, if an exit hole in excess of 24 mm in diameter is produced, the terminal effect inside the vehicle is likely to be considerable as the jet continues into the target with considerable residual energy bringing with it 'spall' or splinters torn off the armour plate. Thus, the performance and effect of the hollow charge round is largely dependent on cone diameter.



Myths of Heat rounds.

HEAT rounds do not depend in any way on thermal phenomena for their effectiveness. In particular, the shaped charge jets do not "melt their way" through armor, only reaching 500-600°C, and instead rely on extreme pressure to force a hole through the armor

Heat rounds do not penetrate then explode which I do have to say at one time I thought was the way they worked.

to make a long story short, HEAT shells (in-game) are APCR and HE shells put together. They have the penetration of a APCR and the splash of a HE shell. So id rather use a HEAT than a HE because i can do dmg to the target even if you cant penetrate it  :arta:

Nihtwaco #4 Posted Nov 23 2012 - 22:09

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Howdy Folks

here are three useful links.

http://en.wikipedia....ti-tank_warhead

http://en.wikipedia....ive_squash_head

http://www.inetres.c...6.html  Current Production US 120mm System and Ammo.

These will give a basic overview. WW II Ammunition was not as reliable or as consistent in effects as Modern ammo. HEAT Rnds used a base Fuze which relied on a clean impact to Function, Hitting an angled plate could cause a delayed function impact or none function impact with the shell whistling off over the Hills. Best HEAT rnd Function was on 90 degree side shots into the area below the Turret ring where the side blast would damaged the tracks while the main jet would go through the ammo racks. Even a Dud rnd might do severe damage if it made it through the Weaker side armor on a PzK III or PzK IV. That depended on shell size, Velocity and remaining energy at impact. Russian 152mm shells were noted for their simple and effective fuzing and resulting large damage effects with both HE and HEAT ammo. US 105mm HEAT was only used as a last ditch defense of gun Positions round with Maybe 6 rnds per gun issued Partialy due to it's High Dud rate. I have not found any indication that 105mm Equiped Shermans carried any more than that. Most Combat reports I have read indicate M1 HE were the rounds being used on most targets.

Man Portable HEAT rounds US 2.85" Rocket and German 88mm Rocket and Panzerfaust series were fairly reliable on side or rear shots much less so on front end shots. This was partialy due to Fuze Function problems and Partially due to lack of Penetration Depth vs Heavy Bow armor. In game the Number of None effect shots I have had with HEAT Rounds is Consistent with Known Battle effects minus the HE Side blast effects the Current HEAT Modeling does not take into account. Enjoy using them but do take your time with your shot setup and Aim point selection.

Razavn #5 Posted Nov 23 2012 - 22:09

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View PostSpyHawk9, on Nov 23 2012 - 21:20, said:

to make a long story short, HEAT shells (in-game) are APCR and HE shells put together. They have the penetration of a APCR and the splash of a HE shell. So id rather use a HEAT than a HE because i can do dmg to the target even if you cant penetrate it  :arta:


Umm...that is wrong and shame on you for spreading false information.

In game HEAT shells more closely resemble AP/APCR and do NOT resemble HE in any way except for that they do not lose penetration over long distances.

AP - Loses some pen over distance, has to pen to do damage, and has 3-5 degrees of armor normalization (makes it slightly easier to pen sloped armor).

APCR - Loses more pen over distance than AP (except for guns in which their main shells are APCR [Tier 10 meds]), has to pen to do damage, and has 3-5 degrees of armor normalization (makes it slightly easier to pen sloped armor).

HE - Does not lose pen over distance, does full damage if it pens, does 1/2 damage - armor (not sure exactly what the formula is) if shell does not pen), does not benefit from normalization, and has a splash radius.

HEAT- Does not lose pen over distance, has to pen to do damage, does NOT benefit from normalization (it is more likely to not pen highly angled surfaces).

Edited by Razavn, Nov 23 2012 - 22:11.


Nihtwaco #6 Posted Nov 23 2012 - 22:12

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Bad Link got posted here is correct one

http://www.inetres.c...eapon/M256.html



Cybergod #7 Posted Nov 23 2012 - 23:53

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View PostSpyHawk9, on Nov 23 2012 - 21:20, said:

to make a long story short, HEAT shells (in-game) are APCR and HE shells put together. They have the penetration of a APCR and the splash of a HE shell. So id rather use a HEAT than a HE because i can do dmg to the target even if you cant penetrate it  :arta:
No I hate to break it to you that is in noway how they work.