the 37mm question?

[panda124c]

Originally posted by Lars Remmen:


Being nitpicky? I just pointed out that I think you are wrong. Tungsten utilized in AP ammo is used to make the projectile hard, light and thus to make the projectile leave the muzzle faster then the ordinary AP round. Not to make the projectile heavier. Since you said (at least the was how I read it) that the reason the US round was heavier was due to tungsten I don't think that is being nitpicky

OK my two cents. If you make a core of tungstan inside a shell (surrounded by a steel/lead jacket) the shell will be heavier than a normal AP round. If you also drive this round at a higher velocity. Then you will get much higher energy in the round. Now an interesting thing happens when this sort of round hits an armor plate, the outer jacket peals off but it imparts the overall energy to the smaller tungstan core giving it a much higher energy per sq inch this much higher energy causing the core to penatrate a much thicher plate. A higher velocity can be achived by using something other than steel/lead for the jacket. Using a pure tungstan round it not feasiable because you wear out the rifleing in the barrel and it's to heavy to achive the velocity. The velocity is important for two reasons it is part of the force equation and the longer a round takes to reach a target the more it drops this caused and accracy problem.

Did I say two cents opps.

[sven]

Originally posted by pbear:


OK my two cents. If you make a core of tungstan inside a shell (surrounded by a steel/lead jacket) the shell will be heavier than a normal AP round. If you also drive this round at a higher velocity. Then you will get much higher energy in the round. Now an interesting thing happens when this sort of round hits an armor plate, the outer jacket peals off but it imparts the overall energy to the smaller tungstan core giving it a much higher energy per sq inch this much higher energy causing the core to penatrate a much thicher plate. A higher velocity can be achived by using something other than steel/lead for the jacket. Using a pure tungstan round it not feasiable because you wear out the rifleing in the barrel and it's to heavy to achive the velocity. The velocity is important for two reasons it is part of the force equation and the longer a round takes to reach a target the more it drops this caused and accracy problem.

Shh! Don't confuse them with facts.... just reduce the American gun.

Did I say two cents opps.

[FrankyVas]

Sven, please refrain from posting again unless you have something constructive to say. One post might have been OK? but you haven't said anything usefull. Most people don't know how a gun's ballistics work and would be interested in learning. If they read your crappy posts they probably won't read on and won't learn.

Frank V.

[AmmoSgt]

OK some simple facts
Iron is atomic number 26 atomic symbol FE
Tugnsten is atomic number 72 atomic symbol W
look it up on any periodic table
Tugnsten is significantly heavier per cubic centimeter than Iron..

Energy is Mass x velocity SQUARED or E=Mc^2

Apples and oranges.. as armor developed ammo to defeat armor developed and not all shells are constructed to be AP types , different AP types are constructed differently , and HE shells are constructed very differently. HE is different from AP just as APCR is constructed different APDS...
Ammo needs to be compared ger 37mm AP v us AP not APCR v APDS .. AT ammo is divided into two Broad Categories, Kinetic Energy and Chemical Energy...BUT even within a broad category , different construction is used to exploit different techniques of penetrating armor, and differing quality and hardness of specfic alloys used makes direct simple comparsions based on even the same spefic class of ammo dificult ..
Add to this that any mismatch of propelent burn speed and barrel lenght severly reduces any assumed advantage of barrel lenght .. even the proportions of the shell and shape drastically effect performance.
The type and number of groves in the rifling and the twist rate effect accuraccy and likelyhood of some ammo designs and types working better and being more stable than others out of the same gun .
Take the US M250cal and the Russian 12.7 the boattail design of the US bullet makes for a superior performance the length to diameter ratio also plays a roll.
As well as i can enumerate the significant factors the Desigh on a Gun and the associates ammo is not cut and dried ..
Amazing synergies happen that are more art and luck than engineering The US 8" How M-1 was one of those amazing happenstance that created an incredibly accurate gun , While the US 175mm was a absolute disaster CEP wise ( Center Error Proable , the way artilery accuracy is measured )
The US 37mm was almost oe of those miracle guns in the eariler versions , and some tweaking turned into a wonder gun for it's caliber.. but it was more a wish and a fluke than a deliberate thing .. The German 37mm was an average gun and useful enough as at the time for what the percived threat was

[sven]

Originally posted by FrankyVas:
Sven, please refrain from posting again unless you have something constructive to say. One post might have been OK? but you haven't said anything usefull. Most people don't know how a gun's ballistics work and would be interested in learning. If they read your crappy posts they probably won't read on and won't learn.

Frank V.

Dear Mr. Vas:

Have you attempted to read any of the older threads on the issue?

Do any of the new guys?

I am always happy to help and have in the past. German Fan tends to whine... a lot.

My opinion!

Have at it!

[Lars Remmen]

Originally posted by pbear:


OK my two cents. If you make a core of tungstan inside a shell (surrounded by a steel/lead jacket) the shell will be heavier than a normal AP round. If you also drive this round at a higher velocity. Then you will get much higher energy in the round. Now an interesting thing happens when this sort of round hits an armor plate, the outer jacket peals off but it imparts the overall energy to the smaller tungstan core giving it a much higher energy per sq inch this much higher energy causing the core to penatrate a much thicher plate. A higher velocity can be achived by using something other than steel/lead for the jacket. Using a pure tungstan round it not feasiable because you wear out the rifleing in the barrel and it's to heavy to achive the velocity. The velocity is important for two reasons it is part of the force equation and the longer a round takes to reach a target the more it drops this caused and accracy problem.

Did I say two cents opps.

All-right...

For the 7.5 cm Pak 40:

AP: Weight 6.8 kg or 14.5 lbs. Muzzel velocity 750 m/s or 2.460 fps.

AP40 (Tungsten cored): Weight 4.1 kg or 9 lbs. Muzzel velocity 930 m/s or 3.050 fps

[Belisarius]

Another swing at it:

Tungsten (funny considering it's a Swedish word, meaning 'heavy rock', but in Swedish it's called 'Volfram' ): density 19.3 kg/dm^3

Iron: density 7.86 kg/dm^3

But tungsten's main physical ability is that it has the highest melting point of all metals (3380ºC). Does this have any importance?

From what I know, tungsten was used in ammo to obtain a projectile with a very hard, heavy core. (hardness does matter when penetrating armor). Depleted uranium is used today for the same reason.

[vex]

I originally Posted:
if you're going to get technical, tungsten is what makes it heavier, heavier then brass,steel,etc.etc. but also alot harder then lead. thereby giving it mass(=force)while not compromising on its hardness (ability to pierce).

a simple (and correct answer) to a simple question to add some more information to a problem. i am a degreed chemist with a master's in chemical engineering and work as such. i could have pointed at the density, atomic weight and boiling point which all point to the same answer in a long winded way but didn't see the point because, that wasn't my point. i would love to have a educated discussion/argument on such a topic but calling me wrong and then stating the same answer in different ways shows that you are being a know-it-all who only cares about trying to be right and not have an intelligible conversation/discussion. this is more of a "jerry springerish" type argument and therefore will take no part in it. their are numerous reasons for the 37mm phenom in SPWAW another could even be the way guns were often tested in WW2 (see "death traps" by cooper) or many other tales of flawed US ordinance tests.

oh, to take a shot at being larsish or svenish. AmmoSgt, your information is quite proper - however, i believe that e=mc2 is not the equation you are looking for, because this is part of eintein's quantum theory where c=the speed of light coeffient.
i believe you were looking for force=massxacceleration. maybe i am wrong?

[Lars Remmen]

Originally posted by vex:
I originally Posted:
if you're going to get technical, tungsten is what makes it heavier, heavier then brass,steel,etc.etc. but also alot harder then lead. thereby giving it mass(=force)while not compromising on its hardness (ability to pierce).

a simple (and correct answer) to a simple question to add some more information to a problem. i am a degreed chemist with a master's in chemical engineering and work as such. i could have pointed at the density, atomic weight and boiling point which all point to the same answer in a long winded way but didn't see the point because, that wasn't my point. i would love to have a educated discussion/argument on such a topic but calling me wrong and then stating the same answer in different ways shows that you are being a know-it-all who only cares about trying to be right and not have an intelligible conversation/discussion. this is more of a "jerry springerish" type argument and therefore will take no part in it. their are numerous reasons for the 37mm phenom in SPWAW another could even be the way guns were often tested in WW2 (see "death traps" by cooper) or many other tales of flawed US ordinance tests.

oh, to take a shot at being larsish or svenish. AmmoSgt, your information is quite proper - however, i believe that e=mc2 is not the equation you are looking for, because this is part of eintein's quantum theory where c=the speed of light coeffient.
i believe you were looking for force=massxacceleration. maybe i am wrong?

A know-it-all? Said you were wrong? No I said I *THINK* you are wrong. And I put that *THINK* into the sentence very deliberately. I've tried to explain why I think so. If you think I am wrong do feel free to explain to me why you think so. If you've allready done so I haven't understood it as such and apologize. I don't mind being proven wrong - it happens to everyone from time to time.

[AmmoSgt]

yes sorry E= mv^2 i think same basic formula only c is indeed specifically the constant for speed of light

[Brummagem]

Well all I know is that Pi is not squared it's round, corn bread is squared.
Seriously thanks for all the tech guys. bottom line though is get that 37 to the backside of the tank and you got a chance.

[Brummagem]

The 37 mm Anti-tank Gun, M3
In 1935 the U.S. Army began the development of an anti-tank gun, a newly conceived field artillery piece whose mission was to defeat the recently developed tanks of that era. Foreign anti-tank guns were studied including the 25 mm French Hotchkiss and the 37 mm German Rhinemetall. In 1937 with World War II imminent, the Ordinance Department issued a requirement for an anti-tank gun weighing less than 1000 lbs so that it could be transported by a jeep. The resultant design was essentially a copy of the 37 mm Rhinemetall with minor modifications. The barrel size was 37 mm with a dropping block breech. Anti-tank ammunition was developed with a projectile velocity of 2900 fps. The small anti-tank gun served as the predecessor of the 37 mm guns for the Stuart light tanks and the M8 armored car. Between 1939 and 1943 over 20,000 37 mm anti-tank guns were manufactured. The M3 37 mm anti-tank gun proved too light a caliber to be effective against tanks in North Africa and Europe. In the Pacific theater the M3 anti-tank gun was more effective against Japanese armor and proved to be an accurate direct fire weapon for stationary hard targets. A large hand crank wheel controls traverse of the barrel while the small knob below it changes gun elevation.
ADDITIONAL TECHNICAL DATA 37 MM ANTI-TANK GUN, M3

Length............10 ft. 10.5 in.
Width..............5 ft. 3.5 in.
Height.............3 ft. 2 in.
Weight.............912 lbs.
Firing Rate........5-20 rounds per minute
Munition...........Fixed HE, AP, APC and Cannister
Projectile Weight 1.5 to 2 lbs.

[sven]

Originally posted by Brummagem:
The 37 mm Anti-tank Gun, M3
In 1935 the U.S. Army began the development of an anti-tank gun, a newly conceived field artillery piece whose mission was to defeat the recently developed tanks of that era. Foreign anti-tank guns were studied including the 25 mm French Hotchkiss and the 37 mm German Rhinemetall. In 1937 with World War II imminent, the Ordinance Department issued a requirement for an anti-tank gun weighing less than 1000 lbs so that it could be transported by a jeep. The resultant design was essentially a copy of the 37 mm Rhinemetall with minor modifications. The barrel size was 37 mm with a dropping block breech. Anti-tank ammunition was developed with a projectile velocity of 2900 fps. The small anti-tank gun served as the predecessor of the 37 mm guns for the Stuart light tanks and the M8 armored car. Between 1939 and 1943 over 20,000 37 mm anti-tank guns were manufactured. The M3 37 mm anti-tank gun proved too light a caliber to be effective against tanks in North Africa and Europe. In the Pacific theater the M3 anti-tank gun was more effective against Japanese armor and proved to be an accurate direct fire weapon for stationary hard targets. A large hand crank wheel controls traverse of the barrel while the small knob below it changes gun elevation.
ADDITIONAL TECHNICAL DATA 37 MM ANTI-TANK GUN, M3

Length............10 ft. 10.5 in.
Width..............5 ft. 3.5 in.
Height.............3 ft. 2 in.
Weight.............912 lbs.
Firing Rate........5-20 rounds per minute
Munition...........Fixed HE, AP, APC and Cannister
Projectile Weight 1.5 to 2 lbs.

I just visited the Ordnance Museum and saw a mint one....

ahhh museum...