Actual Thickness Of Amx-30 Armor

[BabyOlifant]

I've seen several sources quote the AMX-30 as having a steel plate of armor sloped at such a degree that it produced 80mm of steel across the horizontal line of sight.

 

A cursory examination shows this as being much less armor than the Leo 1's (according to an Osprey book, according to Wikipedia) , a tank which is related at least by marriage. Ahah, I thought, this explains why the AMX-30 is so much lighter (36t versus over 42t)! Digging deeper, oh, no, the AMX is smaller in every dimension than the Leopard 1, and that, in fact, were you to make a steel cube of the relevant dimensions of both an AMX and Leopard 1, the AMX-cube would weigh 75% that of the German tank-cube. This isn't a rigorous comparison, but it still raises questions.

 

Further investigating my sources reveals that they all cite either no one at all, or Jane's Main Battle Tanks - Second Edition. Jane's is normally good, but not infallible, so I checked French Google to see if they had anything to say one way or the other. The extra-cheese Internet proved less helpful than the standard variety. Harrumph.

 

It seems at least plausible to me that the line of sight armor thickness figure was misheard, misquoted, or otherwise garbled in translation from one language to another. It sounds like less armor than the tank should have, given its relation to a Leo 1. But maybe not, the French were crazy like that. Can Tanknet give me a confirm/deny on this armor figure? Feel free to take the day off and go to the beach if you can't find anything more authoritative than Jane's. I'm not holding you to anything.

 

Along the way, it was suggested that 80mms of frontal armor was a longstanding requirement for French medium tanks. Does anyone know if this was the case, and if so, what in particular were they trying to protect against?

 

Thanks in advance,

Olifant

[Marek Tucan]

This schematic should show it.

 

EDIT: 80mm should be enough to protect from 75mm-88mm guns with APCBC (for 75 maybe also HVAP), so generally "light tank and old ATG proof", I would say.

 

 

Edited August 13, 2012 by Tuccy

[bojan]

Frontally AMX-30 has slightly less armor then T-54/55. Sides as can be seen are way less. It weights ~same, but has slightly more room inside (less then 1m³)...

So IMO Janes is wrong (again) and diagram, even if not totally accurate is much closer to reality then anything else.

 

With the armor scheme as on pic it would be immune to 85mm AP and HVAP and somewhat proof vs 100mm AP over 1000m range. Fits time period and philosophy.

Edited August 13, 2012 by bojan

[methos]

A cursory examination shows this as being much less armor than the Leo 1's (according to an Osprey book, according to Wikipedia) , a tank which is related at least by marriage. Ahah, I thought, this explains why the AMX-30 is so much lighter (36t versus over 42t)! Digging deeper, oh, no, the AMX is smaller in every dimension than the Leopard 1, and that, in fact, were you to make a steel cube of the relevant dimensions of both an AMX and Leopard 1, the AMX-cube would weigh 75% that of the German tank-cube. This isn't a rigorous comparison, but it still raises questions.

 

The armour thickness of tanks differs from place to place. The Leopard 1 hull armour for example is iirc. 35 mm in the frontal area and 20 mm at the engine. Given the wikipedia values the hull side armour of the AMX-30 is stronger at every place. The turret of the AMX-30 per se is smaller, but the commander's cuppola inceases it's frontal profile and maximum height very much, so that the result is a greater surface than the Leopard 1. Afaik the AMX-30's turret is longer and the tank gun has a longer barrel (and therefore weighs more). The secondary armament (12.7 mm HMG or 20 mm autocannon) also weighs more than that of the Leopard 1.

 

The actual weight difference is only 4 tonnes, the empty AMX-30 weighs 34 tonnes empty, while the Leopard 1 (pre-A1) weighs 38 tonnes empty.

 

I think wikipedia contains some valuable information from C. Foss:

The turret has a maximum armour thickness of 50 millimetres (2.0 in), the armour sloped at 70 degrees on the front plate and 23 degrees on the side, offering protection against 20-millimetre (0.79 in) armour piercing projectiles. The Line-of-Sight armour values are: 79-millimeter (3.1 in) for the front of the hull; 59-millimetre (2.3 in) for the forward sides of the hull; 30-millimetre (1.2 in) for the rear sides and rear of the hull; 15-millimetre (0.59 in) for the hull top and bottom; 80.8-millimeter (3.18 in) for the turret front; 41.5-millimeter (1.63 in) for the turret sides; 50-millimetre (2.0 in) for the turret rear and 20-millimetre (0.79 in) for the turret top.

 

@Tuccy

Source of this drawing and source of the values used there?

Edited August 13, 2012 by methos

[BabyOlifant]

Thanks a lot, Tanknet.

 

EDIT: 80mm should be enough to protect from 75mm-88mm guns with APCBC (for 75 maybe also HVAP), so generally "light tank and old ATG proof", I would say.

 

With the armor scheme as on pic it would be immune to 85mm AP and HVAP and somewhat proof vs 100mm AP over 1000m range. Fits time period and philosophy.

 

This seems to indicate a "have about as much armor as a Panther" philosophy, which makes sense.

 

The turret of the AMX-30 per se is smaller, but the commander's cuppola inceases it's frontal profile and maximum height very much, so that the result is a greater surface than the Leopard 1.

 

I was measuring to top of turret, since the copula doesn't add much weight.

 

The actual weight difference is only 4 tonnes, the empty AMX-30 weighs 34 tonnes empty, while the Leopard 1 (pre-A1) weighs 38 tonnes empty.

 

I had been wondering if that was before or after they added all the appliqué armor to the Leopard.

 

I think wikipedia contains some valuable information from C. Foss:

 

Check the name of the source on la Wik. It's from the Jane's I cited in the OP. If Tuccy's post is to be believed, Jane's is wrong (which wouldn't be the first time).

 

80mm sloped armor seems to make more sense given the context of the AMX-30's development.

Edited August 13, 2012 by BabyOlifant

[methos]

80mm sloped armor seems to make more sense given the context of the AMX-30's development.

 

Actually no. The AMX-30 and Leopard 1 emerged from the same programme. Requirements there were "full protection vs 20 mm". Nothing about tank guns. I can only say that there are various images from th production and prototypes, which IMO speak against tuccy's image. For example some prototypes carried a welded glacis and because of the layout the thickness of the upper plate can be seen - it seems to be less armour than 80 mm. If I compare images from AMX-30 production with images from the Leopard 1 production, then I cannot see any reason why the AMX-30 should have stronger front armour - they appear to have roughly the same amount of front armour.

The weight difference could come from the differences in the layout - meaning equipment carried and the higher amount of side armour.

 

Do you know the turret weight of the AMX-30? The Leopard 2 turret weighs 6 tonnes, while having 5 - 7 cm armour. The AMX-30 turret from tuccy's drawing has more armour than the 12 tonnes turret of the M48... so how much would it weigh? 13 - 14 tonnes? Even if the turret would weigh only 12 tonnes like the one of the M48, then there would not be enough weight left for the hull. The hull would then need to weigh only 24 tonnes... while achieving more than twice the protection of the 32 tonnes hull of the Leopard 1.

[BabyOlifant]

Actually no. The AMX-30 and Leopard 1 emerged from the same programme. Requirements there were "full protection vs 20 mm". Nothing about tank guns. I can only say that there are various images from th production and prototypes, which IMO speak against tuccy's image. For example some prototypes carried a welded glacis and because of the layout the thickness of the upper plate can be seen - it seems to be less armour than 80 mm. If I compare images from AMX-30 production with images from the Leopard 1 production, then I cannot see any reason why the AMX-30 should have stronger front armour - they appear to have roughly the same amount of front armour.

The weight difference could come from the differences in the layout - meaning equipment carried and the higher amount of side armour.

 

Do you know the turret weight of the AMX-30? The Leopard 2 turret weighs 6 tonnes, while having 5 - 7 cm armour. The AMX-30 turret from tuccy's drawing has more armour than the 12 tonnes turret of the M48... so how much would it weigh? 13 - 14 tonnes? Even if the turret would weigh only 12 tonnes like the one of the M48, then there would not be enough weight left for the hull. The hull would then need to weigh only 24 tonnes... while achieving more than twice the protection of the 32 tonnes hull of the Leopard 1.

 

That honestly doesn't seem that unreasonable. The Leo 1 has 70mm of sloped armor, the AMX has 80 (maybe). Those are fairly similar figures. Where the AMX gets a great advantage is in its much greater slope.

 

Given the layout of the AMX-30, the turret might well weigh half that of the chassis; the chassis is very small.

 

I merely supposed that it would make more sense for the AMX's protection to be comparable with that of the Leopard 1's. Accepting Jane's line about the armor being 80mm LOS means you have to accept the idea that the AMX has only a 30mm thick front plate (sloped back 68 degrees), less than half the thickness of the Leopard 1. This sounds odd, given that they once shared a development program.

 

The AMX-30 takes up roughly 75% of the volume of a Leopard 1 (not including the copula, which was probably very light), but is 90% as heavy. Is it too far-fetched to surmise that the protection might be better?

[Marek Tucan]

NOTE: Diagrams come from bojan's gallers and are apparently from Russian books on armor, but they fit rather well with known facts and known demands for protection.

 

Actually no. The AMX-30 and Leopard 1 emerged from the same programme. Requirements there were "full protection vs 20 mm". Nothing about tank guns.

Despite all the "armor has no use because of HEAT", both French and German designers knew all too well (and the armies even better) that frontal protection is needed at least to "obsolete" threats (APBC/APCBC formed most of WarPac loadouts throughout 1950s and 1960s). Thus both Leo 1 and AMX were supposed to protect frontally vs. older antitank/tank guns and at long range (1000m+) against 100mm (turret front at least for Leo might have been better than that, thanks to the mantlet). 20mm requirement was for minimal all-round protection, not for maximal frontal protection.

 

I can only say that there are various images from th production and prototypes, which IMO speak against tuccy's image. For example some prototypes carried a welded glacis and because of the layout the thickness of the upper plate can be seen - it seems to be less armour than 80 mm

Seems? 80mm isn't too thick. Never mention that depending ont he purpose, prototypes are often built of mild steel or other substitutes (see M1E1 Abrams for example, with additional steel plates welded on to represent weight of improved turret armor).

 

. If I compare images from AMX-30 production with images from the Leopard 1 production, then I cannot see any reason why the AMX-30 should have stronger front armour - they appear to have roughly the same amount of front armour.

And nobody claims otherwise. Leopard 1 is credited with 70mm glacis.70mm SHS/HHS sandwich (or whatever is in there) would be at least comparable to 80mm cast steel. turret armor of Leo is thinner, but frontally that is made up by a large mantlet. In the end result, the protection of both tanks was rather similar, maybe a bit better with Leo 1, but probably not significantly.

 

 

 

 

 

 

The weight difference could come from the differences in the layout - meaning equipment carried and the higher amount of side armour.

 

Do you know the turret weight of the AMX-30? The Leopard 2 turret weighs 6 tonnes, while having 5 - 7 cm armour. The AMX-30 turret from tuccy's drawing has more armour than the 12 tonnes turret of the M48... so how much would it weigh? 13 - 14 tonnes? Even if the turret would weigh only 12 tonnes like the one of the M48, then there would not be enough weight left for the hull. The hull would then need to weigh only 24 tonnes... while achieving more than twice the protection of the 32 tonnes hull of the Leopard 1.

 

M48 turret has significantly more armor on the front and on sides than both, it is also larger, so with more surface to cover.

 

 

 

 

[methos]

That honestly doesn't seem that unreasonable. The Leo 1 has 70mm of sloped armor, the AMX has 80 (maybe). Those are fairly similar figures. Where the AMX gets a great advantage is in its much greater slope.

[...]

The AMX-30 takes up roughly 75% of the volume of a Leopard 1 (not including the copula, which was probably very light), but is 90% as heavy. Is it too far-fetched to surmise that the protection might be better?

 

You are saying that the AMX-30 has to be better armoured because it has a higher weight per volume. I agree with that, even though I think your approximation is too rough. But you say that Jane's values speak against the AMX-30 having better armour.

The values from Jane's however show that the hull side, the turret front, the rear and the lower hull are better armoured than the Leopard 1, only the glacis and the turret sides are better armoured on the Leopard 1. And this could be the reason for the higher weight-per-volume ratio (density) of the AMX-30... not the frontal armour, but other places.

 

The drawing attributes the AMX-30 not only with better armour than the Leopard 1, but also than the T-55, T-62, M60 and M60A1. Think about it.

 

German literature (Spielberger) claims that the Leopard 1 proved to be better protected in the FINABEL comparative trials lead by Italy.

 

I merely supposed that it would make more sense for the AMX's protection to be comparable with that of the Leopard 1's. Accepting Jane's line about the armor being 80mm LOS means you have to accept the idea that the AMX has only a 30mm thick front plate (sloped back 68 degrees), less than half the thickness of the Leopard 1. This sounds odd, given that they once shared a development program.

 

The requirements were shared. Nothing else.

 

Despite all the "armor has no use because of HEAT", both French and German designers knew all too well (and the armies even better) that frontal protection is needed at least to "obsolete" threats (APBC/APCBC formed most of WarPac loadouts throughout 1950s and 1960s). Thus both Leo 1 and AMX were supposed to protect frontally vs. older antitank/tank guns and at long range (1000m+) against 100mm (turret front at least for Leo might have been better than that, thanks to the mantlet). 20mm requirement was for minimal all-round protection, not for maximal frontal protection.

 

Could you please provide a source for this statement? I have read several books about the Leopard 1, including various German-language ones, and not a single one claimed that the protection requirement as larger than "20 mm close range" or "medium caliber rounds".

The Leopard 1 turret is between 50 and 70 mm thick, that's not enough against "obsolete threats" like the 85 mm tank gun of the T-34.

 

And nobody claims otherwise. Leopard 1 is credited with 70mm glacis.70mm SHS/HHS sandwich (or whatever is in there) would be at least comparable to 80mm cast steel. turret armor of Leo is thinner, but frontally that is made up by a large mantlet. In the end result, the protection of both tanks was rather similar, maybe a bit better with Leo 1, but probably not significantly.

 

No laminated armour in 1965. The glacis is a single 70 mm steel plate, 140 mm due to slope, the turret is 50 to 70 mm thick. Compare this to the claimed AMX-30 glacis 80 mm at 68° (213 mm) and 309 mm turret armour.

The mantlet of the Leopard 1 is 60 mm at 55° - 104 mm LOS... only half as thick as the claimed AMX-30 glacis or a third of the claimed AMX-30 turret.

 

 

M48 turret has significantly more armor on the front and on sides than both, it is also larger, so with more surface to cover.

 

... and at the same time the Leopard 1 and AMX-30 carry more FCS equipment and larger guns.

[Marek Tucan]

Could you please provide a source for this statement? I have read several books about the Leopard 1, including various German-language ones, and not a single one claimed that the protection requirement as larger than "20 mm close range" or "medium caliber rounds".

The Leopard 1 turret is between 50 and 70 mm thick, that's not enough against "obsolete threats" like the 85 mm tank gun of the T-34.

 

No laminated armour in 1965. The glacis is a single 70 mm steel plate, 140 mm due to slope, the turret is 50 to 70 mm thick. Compare this to the claimed AMX-30 glacis 80 mm at 68° (213 mm) and 309 mm turret armour.

The mantlet of the Leopard 1 is 60 mm at 55° - 104 mm LOS... only half as thick as the claimed AMX-30 glacis or a third of the claimed AMX-30 turret.

100 mm was considered medium caliber. 120mm+ was large caliber.

Leopard 1 hull glacis is 70mm, Paul Lakowski seems to imply in his Armor technology (if I read it correct) that this is composed of "triple hardness steel" array - a HHS plate welded on face-hardened? RHA. This would give better protection that simple geometry would imply (esp. connected with slope effect) vs. AP and HVAP - definitely vs. 85mm AP (Hetzer's 60mm@60° RHA glacis managed it already), most likely at range against 100mm as well (HHS layer would possibly reduce the "biting in" effect of blunt penetrators, AMX-30's cast armor nmight suffer from it more).

 

Turret is (from frontal arc) 50-60mm at extreme angles and a massive and wide (and sloped) mantlet. Mantlet might withstand 100mm AP from up close púrobably, overall front 60° would withstand it at 1 km at worst.

AMX-30 armor array is very similar. Greater thickness of glacis and greater slope on one hand, cast armor on the other (90% of protection, roughly, compared to same thickness RHA)... Both tanks ought to be pretty matched in their frontal protection. Given that the requirements were similar, end result would be again comparable.

 

Mantlet - AMX-30 is smaller, and looks less well shaped than Leo's wedge shape. Without having turret taken apart it is hard to tell how much of turret front is overlapped by it, but it would seem that less than in Leopard's case.

 

 

... and at the same time the Leopard 1 and AMX-30 carry more FCS equipment and larger guns.

 

I was responding to your assertion that AMX-30 turret would have more protection than M48. That is not the case. While there is less slope, M48 has more "raw force" - thicket turret front and mantlet combination. While lower angle demands more armor, more armor helps against overmatching.

[methos]

Paul L. is talking about the spaced turret of the Leopard 1A3 when he mentions triple-hardness steel. This technology however was not available in 1965 and also not used in the hull.

 

Turret is (from frontal arc) 50-60mm at extreme angles and a massive and wide (and sloped) mantlet. Mantlet might withstand 100mm AP from up close púrobably, overall front 60° would withstand it at 1 km at worst.

 

This is Paul L.'s estimate only. Literature and the cut-through Leopard 1s that can be seen in museums speak against his estimations for the Leopard 1 armour. He also said that the Leopard 1A5 would use new and stronger armour than the previous models, but de facto the armour of the Leopard 1A5 is the same as used on the Leopard 1A1A1.

[DKTanker]

... and at the same time the Leopard 1 and AMX-30 carry more FCS equipment and larger guns.

How are the Leo 1 and AMX-30 carrying more FCS equipment than the M48?

[BabyOlifant]

I think your approximation is too rough.

 

So do I. I'm just eyeballing it. The tanks are roughly similar, though, so it shouldn't be too far off (if the armor protection were the same).

 

But you say that Jane's values speak against the AMX-30 having better armour.

 

They absolutely speak against the AMX-30 having anything like the kind of armor that the Leo 1 has. Given the Jane's values, the Leopard 1 has 75% more glacis armor than the AMX. That's... Kind of odd.

 

The drawing attributes the AMX-30 not only with better armour than the Leopard 1, but also than the T-55, T-62, M60 and M60A1. Think about it.

 

The AMX-30 is about the same size and weight as a T-55, but can't have as good/better armor?

 

As for it having better armor than the T-62 or M60, that's just nonsense. The M60 has siliceous cored armor, which is thicker, anyway.

 

If you compare medium tanks of the era, the AMX has very comparable protection to everything else (except the Leo 1, which lags behind):

 

 

T-55

Front Glacis: 120mm (240mm effective)

Front Turret: 200mm mantlet LOS

 

 

Centurion Mk 10

Front Glacis: 121mm (222mm effective)

Front Turret: 165mm LOS (200mm mantlet)

 

 

M48A3 Patton III

Front Glacis: 110mm (220mm effective)

Front Turret: 178mm (206mm effective, 228mm mantlet)

 

 

Leopard 1

Front Glacis: 70mm (140mm effective)

Front Turret: 52mm (123mm effective, 100mm mantlet)

 

 

AMX-30

Front Glacis: 80mm (214mm effective)

Front Turret: 80mm (274mm effective, 150mm mantlet)

 

The AMX-30 has armor protection just a bit less extensive than a Patton, given the values from the drawing. That's accepting that all armor types provide equivalent protection (they don't).

[DKTanker]

The M60 has siliceous cored armor, which is thicker, anyway.

That is incorrect, it has simple cast armor.

[BabyOlifant]

Lemme check Hunnicutt's to make sure I didn't read it wrong.

 

EDIT: Whoops, looks like they did try it on some of the prototypes, but the actual production versions were a big cast block. That is why the hull is shaped differently than the Patton, though.

Edited August 14, 2012 by BabyOlifant

[methos]

They absolutely speak against the AMX-30 having anything like the kind of armor that the Leo 1 has. Given the Jane's values, the Leopard 1 has 75% more glacis armor than the AMX. That's... Kind of odd.

 

But it has 20% more turret front armour, 60+% frontal side armour, 50% rear side armour.

 

Let's see:

Turret armour

Chieftain

- 380 to 400 mm

AMX-30 (the non-Jane's version)

- 309 mm

M60A3

- 272 mm

T-62

-240 mm

T-55

-200 mm

M48

-170 - 180 mm

Pz 68

-165 mm

AMX-30

-81 mm

Vickers Mk1

-80 mm

Leopard 1

-60 mm

 

So, what do you think is more reasonable: Assuming that a tank designed with a very low requirement for protection and the lowest weight (except the T-55) has the second best turret armour (and third best glacis armour) or that the tank is placed on a very low place when it comes to armour protection? If we compare the AMX-30 with the values from the image to other tanks, then the AMX-30 is the holy grail of tank design...

[EchoFiveMike]

How much did the 105mm Modele F1 weigh compared to L7? IIRC, F1 was medium pressure, which was why it was used in Super Sherman? S/F....Ken M

[methos]

How much did the 105mm Modele F1 weigh compared to L7? IIRC, F1 was medium pressure, which was why it was used in Super Sherman? S/F....Ken M

 

Super Sherman did use the 105 mm gun from the AMX-13 afaik. The F1 is at least capable of firing the 105 mm DM63 (M426) ammunition.

[Tomas Hoting]

How much did the 105mm Modele F1 weigh compared to L7? IIRC, F1 was medium pressure, which was why it was used in Super Sherman? S/F....Ken M

 

According to Jane's the AMX-30's CN105F1 has an overall weight of 2,470 kg (which is probably the weight of the complete gun mount). For the L7 (as used in the Leopard 1) the weight of the gun mount w/o the mantlet is 2,300kg and with the gun mantlet is 2,950kg. Pressure-wise, the CN105F1 is in the same league as the L7.

 

The M51 Super Sherman's 105mm gun is a bit strange. It's usually called the D1504, but one older Spanish CESEDEN document calls it the D1508. It's usually reported to be a 44-calibre version (the CESEDEN document says it's a 51-calibre gun) of the AMX-30's 56-calibre CN105F1 gun, fitted with a muzzle break. This muzzle break is completely different to the one of the 105mm CN105-57 gun mounted in AMX-13s or the Kürassier.

 

When fired from the Sherman's gun, the OCC 105 F1 HEAT projectile (or "Obus-G") is reported to have a muzzle velocity of 905m/s.

Edited August 14, 2012 by Tomas Hoting

[dejawolf]

well, leopard 1 hull is 6.94m, while AMX-30 hull is 6.59m that's a lot of extra steel. mostly this is because the AMX-30 has a smaller and much less powerful powerpack than the leopard 1.

so this would account for some of the difference in weight.

i haven't heard a lot of good things about the AMX powerpack either. a soldier in the spanish army told me that it used to break down all the time.

Edited August 14, 2012 by dejawolf

[Harkonnen]

 

Chieftain

 

 

[BabyOlifant]

But it has 20% more turret front armour, 60+% frontal side armour, 50% rear side armour.

 

Let's see:

Turret armour

Chieftain

- 380 to 400 mm

AMX-30 (the non-Jane's version)

- 309 mm

M60A3

- 272 mm

T-62

-240 mm

T-55

-200 mm

M48

-170 - 180 mm

Pz 68

-165 mm

AMX-30

-81 mm

Vickers Mk1

-80 mm

Leopard 1

-60 mm

 

So, what do you think is more reasonable: Assuming that a tank designed with a very low requirement for protection and the lowest weight (except the T-55) has the second best turret armour (and third best glacis armour) or that the tank is placed on a very low place when it comes to armour protection? If we compare the AMX-30 with the values from the image to other tanks, then the AMX-30 is the holy grail of tank design...

 

I'm pretty sure your armor figures at least for the Patton III and Leo I are wrong. I'll let others on the board confirm/deny them, though, since I'm not so confident as to just revise yours completely.

[ramontxo]

Could the AMX-30 be adapted to have the american AVDS diesel motor as carried by the m-48 Pattons?

Edited August 15, 2012 by ramontxo

[Tomas Hoting]

Could the AMX-30 be adapted to have the american AVDS diesel motor as carried by the m-48 Pattons?

 

Yes, as in case of the Venezuelan AMX-30V. Other countries' upgrades included MTU or Renault (Mack) diesels.

Edited August 15, 2012 by Tomas Hoting

[RETAC21]

 

i haven't heard a lot of good things about the AMX powerpack either. a soldier in the spanish army told me that it used to break down all the time.

 

Very bad transmission, got changed when modernised with German diesels, but the tanks didn't last long and were totally ran down, there was a suggestion that they be donated to Colombia, but the Colombians had the good sense to turn it down.