armor protection against british 2 lber and french 47 mm

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herrlabe sr1
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armor protection against british 2 lber and french 47 mm

#1

Post by herrlabe sr1 » 07 Jun 2005, 00:06

Battle of france 1940
How effective was armor protection against these weapons ? At what range were they effective against german armor?

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Markus Becker
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#2

Post by Markus Becker » 07 Jun 2005, 01:20

The glacis plate of the Pz.III was 30mm strong the one of the Pz.38(t) and Pz.35(t) just 25mm.
The 2-pdr will penetrate this at 1000 yards, the 47mm/L53 gun at 1500 meters, even the 25mm AT-gun will be effective at 500m and less.


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David Lehmann
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#3

Post by David Lehmann » 07 Jun 2005, 01:25

Hello,

Canon de 47mm L/53 Mle1937 (SA37)
Caliber : 47x380R mm
Crew : 1 NCO + 5 men
Weight : 1070kg
Length : 4.10m
Width : 1.62m
Height : 1.10m
Barrel length : 2497mm (2350mm rifling)
Rate of fire : 15-20 rpm
Traverse : 68°
Elevation : -13° to +16.50°
Telescopic sight : 4x (field of view 10.13°, + reticle, adjustable drum up to 3500m)
V° : 855 m/s
Practical AT range : 1000m

This AT gun was the best AT gun on the battlefield in 1940, after the 8.8cm Flak18 used in AT role and perhaps the best one before the arrival of the 5.0cm Pak38. It exceeded widely the German 3.7cm PaK in terms of penetration and was also superior to the Czech made 4.7cm AT gun. The French army had about 1200 of them in service in May 1940, they were depending from the artillery regiments and not all came into service. Initially a BDAC should have included 12 47mm AT guns but due to the lack of guns this number was reduced to 8. The Laffly S15T or Laffly W15T (and sometimes Citroën-Kégresse P17 and Unic P107) generally towed the 47mm Mle1937 AT gun if the battery was not horse drawn. An example of report concerning the 47mm Mle1937 AT gun : the French 18th infantry division on the Aisne river on 9-10th June 1940 faced the 10.ID, 26.ID, the SS "Polizei" and elements of the 6.PzD. First they stopped all the German assaults in part thanks to their good supporting artillery and took about 800 German POWs, then they had to pull back because of the collapse of the 2nd infantry division facing two Panzerdivisionen more west. During the retreat, one 47mm SA37 gun destroyed successively 3 moving German tanks at 1500m. Of course that gives not much info in terms of penetration, these tanks could be PzIs as well as PzIVs but the gunsight, accuracy and crew of this gun seem to be rather good ones.
About 823 4.7cm Pak181/182(f) (captured on the front or in factories / repaired / newly built) were used after the campaign of France by the Germans. The Germans produced also a dedicated 4.7cm APCR shell for this gun. But already in May/June 1940 some of the captured guns were immediately used against French tanks, especially the dreaded Renault B1bis. The German reports indicate that 1226 shells were fired with these booty guns furing the battle of France. General Heinz Guderian himself in his memories ("Achtung Panzer !") indicates that he led the fire of a captured French 47mm AT gun against a Renault B1bis.


Ammunitions :
Obus de rupture Mle1936 (APCBC) - in German service : Pzgr 178(f) -
Caliber : 47x380R mm
Weight of projectile : 1.726 kg (1.710 kg without ballistic cap)
Length of projectile : 192 mm (APC 144.5mm + BC 92mm, total length of the shell : 555.5mm)
V° = 855 m/s
The ballistic cap screwed on the APC is in magnesium, resulting in a burning and brilliant lightning at the impact point, helping somewhat in the aiming.

Penetration :

French tests with Mle1936 APCBC (source : French Ministry of Defence, 24th September 1939)
0 meters = 110mm /0°
100 meters = 106mm /0°
200 meters = 101mm /0°
300 meters = 97mm /0°
400 meters = 93mm /0°
500 meters = 89mm /0°
600 meters = 85mm /0°
700 meters = 82mm /0°
800 meters = 78mm /0°
900 meters = 75mm /0°
1000 meters = 72mm /0°
1100 meters = 68mm /0°
1200 meters = 65mm /0°
1300 meters = 62mm /0°
1400 meters = 59mm /0°
1500 meters = 57mm /0°
1600 meters = 54mm /0°
1700 meters = 51mm /0°
1800 meters = 49mm /0°
1900 meters = 47mm /0°
2000 meters = 45mm /0°

German tests with 4.7cm Pzgr. 178(f) mH (source : Thomas Jentz) :
100 meters = 57mm /30°
500 meters = 50mm /30°
1000 meters = 42mm /30°
1500 meters = 36mm /30°

The penetration data for the French 47mm SA37 L/53 AT gun is positioned between the penetration data of the 4.7 cm PaK36(t) and 5.0 cm PaK38, where it should be regarding shell weights and muzzle velocities. German data tells a penetration of 36mm at 1500m and 30° hit angle. This was sufficient to penetrate any German 1940 tank armor on this distance and angle.

To compare the German data for the 5.0 cm Pak38 and 47mm SA37 L/53 AT gun for 30° angle :
At 100m : 69mm (PaK38) and 57mm (SA37)
At 500m : 59mm (PaK38) and 50mm (SA37)
At 1000m : 47mm (PaK38) and 42mm (SA37)
Regarding that the 5.0cm Pzgr.39 had 0.330 kg more weight than the 4.7cm Mle1936 and only 20m/s less muzzle velocity this makes sense.

Obus explosif Mle1932 M39 (HE) - in German service : Pzgr 181(f) -
Caliber : 47x380R mm
Weight of projectile : 1.410 kg (142g explosive)
V° = 590 m/s
Modified Mle1932 HE projectile, usually with a Gaba Mle1932 fuze.

ORGANIZATION OF A MOTORIZED BDAC (Batterie Divisionaire Anti-Char = AT divisional battery)

Command platoon
• 1x commander (captain), 1 NCO, 2 brigadiers, 6 gunners, 7 drivers = 17 men
• 1x liaison vehicle
• 1 all terrain liaison vehicle
• 1x truck
• 4x motorcycles

Guns sections (4 sections)
• 4 officer (lieutenants), 12 NCOs, 12 brigadiers, 8 master gunners, 60 gunners, 32 drivers = 128 men
(including 4 messengers and 16 observers / LMG gunners)
• 8x 47mm Mle1937 AT guns and 8x FM Mle1924/29 LMGs
• 6x truck (4 trucks transporting the signal equipment [8 telephone sets, 4 four-way switchboards, 8 km of
cable and 4 radio sets], the observation equipment and the 8 LMGs)
• 8x all-terrain light tractors towing the guns (and carrying 40 shells)
• 2x all-terrain light tractors transporting ammunition + 2 ammunition trailers
• 4x all terrain liaison vehicle
• 4x motorcycles (for the messengers)
• 4x lorries (2 lorries transporting 350 AT mines each = 700 AT mines)

General services
• 5 NCOs, 2 brigadiers, 15 gunners, 6 drivers = 28 men
• 2x all-terrain heavy recovery tractors
• 1 truck
• 3 lorries
• 1 trailer (field kitchen)

The armament is composed of 8 AT guns (each with 200 shells), 8 LMGs, 700 AT mines and small arms (carbines, pistols etc.).
ORGANIZATION OF A HORSE-DRAWN BDAC (Batterie Divisionaire Anti-Char = AT divisional battery)

Command platoon
• 1x commander (captain), 1 NCO, 2 brigadiers, 6 gunners, 1 horse driver, 9 driver = 20 men
• 4x horses
• 2x liaison vehicles
• 1x truck
• 2x all terrain tractors (used for emergency purposes to tow the guns)
• 4x motorcycles

Guns sections (4 sections)
• 4 officer (lieutenants), 12 NCOs, 12 brigadiers, 8 master gunners, 60 gunners, 52 horse drivers, 4 drivers
= 152 men (16 observers / LMG gunners)
• 120x horses
• 8x 47mm Mle1937 AT guns and 8 caissons, 8x FM Mle1924/29 LMGs
• 2x truck and 2x lorries (transporting ammunition, the signal equipment [8 telephone sets, 4 four-way
switchboards, 8 km of cable and 4 radio sets], the observation equipment and the 8 LMGs

General services
• 5 NCOs, 3 brigadiers, 9 gunners, 16 horse drivers = 33 men
• 24x horses
• 4x wagons (including one field kitchen)
• 1x bicycle (transported on a truck during movements)

The armament is composed of 8 AT guns (24 shells in the limber, 72 shells in the caisson and each section has a truck with 80 shells per gun = 176 shells per gun), 8 LMGs and small arms (carbines, pistols etc.).

Canon de 47mm L/53 TAZ Mle1939 (SA39)
The 47mm Mle1939 TAZ (TAZ = triflèche tous azimuts) had a new 3-trails carriage for a 360° traverse (instead of 68° for the Mle1937), pneumatics to be towed at 60 km/h (instead of 25 km/h for the Mle1937 in a motorized battery or 8 km/h for a horse-drawn battery, which had wheels with rubber tyre) and a flash hider to make the gun more discreet. This gun should have replaced the 47mm Mle1937 for September 1939. A few 47mm Mle1939 guns were probably used during June 1940.


LAFFLY W15 TCC (CC = chasseur de chars = tank destroyer)
The Laffly W15 TCC has been produced in the May-June panic. A prototype has been tested during the Phoney war, and was fully armored. The early May engagements revealed the need for a self-propelled AT gun, and W15 chassis were requisitioned to receive 47mm L/53 Mle37 AT guns. Only the first vehicles were totally armored, for the others, armored plates were put to protect the front part of the vehicle and two small other plates were added to the conventional shield of the AT gun on the rear. 70 were operational by the end of May 1940 and saw action. They were issued to 14 anti-tank batteries (BACA = batterie d'anti-chars automoteurs) of 5 vehicles. Deployed in Abbeville for example but they had no Panzer to be opposed to there and they gave outstanding results on the Loire defenses but had little impact on the whole war. They proved to be very successful, lightly armored but fast and adapted to hit and run tactics. The 54th BACA commanded by lieutenant Brussaux for example, engaged from 5th June 1940 on, destroyed 28 German tanks and 5 German armored cars in 8 days.
Weight : 4.96t
Crew : 3 men (an NCO, a gunner and a driver)
Maximum armor : 12-15mm
Maximum speed : 48 km/h (4 cylinders, 2300 cm3, 56 hp)
Armament : a 47mm SA37 L/53 AT gun (270° traverse towards rear, 30 shells) and a FM 24/29 AAMG (1000 rounds) – the crew has also a Thompson SMG with 500 rounds among other misc light armament.
ORGANIZATION OF A BACA (batterie d'anti-chars automoteurs = self-propelled AT battery)
• Tank destroyer platoon
--o 1x Laffly V15R all-terrain liaison vehicle (with a FM 24/29 AAMG with 1000 rounds and a Thompson SMG with 500 rounds)
--o 5x Laffly W15 TCC (each 1 47mm SA37 AT gun with 30 shells, 1 FM 24/29 AAMG with 1000 rounds and 1 Thompson SMG with 500 rounds)
--o 3x Unic TU1 tractors with 3 Mle1937 infantry trailer, each tractor and trailer carrying 200 shells of 47mm ammunition (each 1 Thompson SMG with 500 rounds)
--o 2 motorcycles

• 25mm AA platoon
--o 3x 25mm Mle1939 Hotchkiss AA guns each towed each by a Laffly W15 T (towing the gun and carrying ammunition and the crew)
--o 1x extra Laffly W15 T used for recovery purpose and extra ammuntion
--o 1x 5t lorry transporting eighty cases of forty 25mm ammunition (3200 shells)
--o 1x liaison vehicle
--o 2x trucks (and 2 FM 24/29 LMGs)
--o 2x motorcycles
--o 1x bicycle (transported on a truck during movements)

• Battery general services
--o 1x Laffly S25 T (towing/repair vehicle)
--o 2x trucks
--o 2x lorries
--o 1x trailer (field kitchen)

==> 3 officers, 21 NCOs and 64 men = 88 soldiers and the armament consists in 5 self-propelled AT guns (150 shells per gun), 3 25mm AA guns, 8 LMGs, 9 Thompson SMGs and other small arms (carbines, pistols etc.).

That's it :)

Regards,

David

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David Lehmann
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#4

Post by David Lehmann » 07 Jun 2005, 01:31

More about French AT guns ....

In a classical French infantry division there are theoretically 52-56 25mm AT guns and 8 47mm AT guns for a total of 60-64 AT guns :
• 12x 25mm SA34/SA37 AT guns in each of the 3 infantry regiments :
--o 2 in each of the 3 infantry battalions
--o 6 in the regimental heavy company
• 12x 25mm SA34/SA37 AT guns in the divisional AT company (CDAC)
• 2x 25mm SA34/SA37 AT guns in the divisional training centre (CID)
• 3-6x 25mm SA34/SA37 AT guns in the reconnaissance battalion (GRDI)
• 8x 47mm Mle1937 or 75mm Mle1897/33 AT guns in the BDAC (AT divisional battery)

Many divisions had no CDAC or CID and many had not the theoretical numbers of AT guns, some had only a dozen. Several divisions had also no 25mm AT guns but used instead the 37mm TR16 infantry gun in AT role.


Canon de 25mm SA Mle1934 (Hotchkiss) and SA-L Mle1937 (Puteaux) L/72
Caliber : 25x194R mm
Crew : 1 NCO + 5 men (+ 1 driver)
Weight : 480kg (SA34 carriage) or 300kg (SA37 carriage, L = light)
Length : 3.71m
Width : 1.05m
Height : 1.10m (at the shield)
Protection : the shield is 7mm thick
Barrel length : 1.80m
Rate of fire : 25 rpm against fixed target and 15 rpm against moving target
Traverse : 60°
Elevation : -5° to +15°
Telescopic sight : 4x (L.711 telescopic sight, with a 3450m range drum, field of view 10.13°, V reticle)
V° : 920 m/s
Practical range : 800m (heavy armored vehicles), 1000m (medium armored vehicles) and 1500m (light armoured vehicles and softskins)
Penetration : 40mm/0° at 500m; 32mm/35° at 200m
Accuracy : at 800m H+L = 80+80 = 160cm

The French 25mm AT guns were very modern in 1934. About 4500 of these guns were in service in May 1940. They were especially known as being very discreet, the flash hider used on them made them difficult to spot according to both French and German AARs. They proved to be very accurate guns, and able to destroy all the German tanks up to 800m if the impact angle was good enough. Only the PzIV Ausf.D at long range was tricky to be engaged by the 25mm AT gun in May/June 1940 if not at close range. In the first 500m the penetration efficiency was at least equal to the penetration of the 3.7cm L/45 PaK and at longer range the KE felt slightly more rapidly due to the lightweight projectile. The Germans captured such guns in large numbers in 1940 and used them in secondary roles as coastal defence and in some garrisons. Finland used also about 240 of these AT guns.
There were theoretically 12 of these AT guns in each French infantry regiment in 1940 but several regiments had only 4 or no AT gun at all. For example the 55th infantry B series division at Sedan had no AT guns in its infantry regiments, 12 AT guns in divisional AT company, a total of 12 AT guns for the whole division (20-25% of the number of the paper). For the 71st infantry division the situation was even worse with only 8 AT guns in the same conditions. These units were also deployed on an overstretched front of 20-30 km whereas a division should defend a 5-7 km wide front. The 37mm TR infantry gun was often still in service even in AT role. The 25mm AT gun was lacking HE shells to neutralize human/soft targets and therefore the 37mm TR infantry gun was still liked since it could fire HE shells. About 220 25mm AT guns were also given to the British Expeditionnary Force (BEF) to increase its firepower, in exchange the British gave the French some Boys AT rifles which were not efficient and had a weaker penetrating power than the Hotchkiss 13.2mm HMG. The two ‘infanterie de l’air’ companies and several reconnaissance groups used some of these AT rifles. Each 25mm AT gun crew had 72 AP/APT shells immediately available and a total of 156 AP/APT shells per AT gun in a French 1940 infantry regiment. In typical infantry or cavalry units the 25mm AT guns were generally towed behind a Mle1937 infantry or cavalry trailer with horses. On the front the Renault UE tractor generally towed them. In motorized infantry regiments the towing vehicle was also often the Renault UE tractor and for long-range movements various halftracks and trucks were used. The AT guns could also be directly transported on a truck or towed on additional "wheels" (train rouleur). In the divisional AT company/squadron of motorized units the official towing vehicle could be the Laffly V15T in cavalry units or the Latil M7 T1 in infantry units. The Unic TU1 was also used for that task.
One single 25mm AT gun from 18e GRCA destroyed quickly 7 German tanks of the 1.PzD in Gravelines on 24th May. During the battle of Gembloux, the French AT gunner Louis Brindejonc (2e RTM) illustrated himself by destroying 7 German tanks including one command tank of a German colonel. In front of Stonne a Panzer IV from 10.PzD was knocked out by the 25mm AT gun of sergeant Durand (67e RI) etc. There are many examples of this gun destroying German tanks. Quoted from the German brigade general Kühne : "The accuracy of the 25mm SA34/37 is very good. The front hull armor of the Panzer III has been easily penetrated by the excellent French 25mm SA34/37 gun. Trials with booty guns proved that the French 25mm AT gun is superior to the German 3.7cm PaK. This 25mm AT gun is very hard to spot because the flash is invisible (flash hider)."


Ammunitions :
Cartouche de 25mm Mle1934 à balle perforante (AP) - in German service : Pzgr 114(f) -
Caliber : 25x194R mm
Weight of projectile : 0.320 kg (steel/tungsten core)
Length of projectile : 109 mm
V° = 920 m/s (charge normale = 137g propellant powder)

Cartouche de 25mm Mle1934 à balle traçeuse perforante (APT) - in German service : Pzgr 115(f) -
Probably white tracer, tracer effect up to 2000m.

Cartouche de 25mm Mle1934 à balle traçeuse perforante (APT) - in German service : Pzgr 116(f) –
Red tracer, tracer effect up to 2000m.

The 2.5cm Pak was rated by Germans to penetrate any German tanks during battle of France up to 800m, if the impact angle was good enough.


German tests :
The test was carried out 1/8-1941 with a 2,5cm KwK 121(f) by HWA on a 120 kg/mm2 armor plate.
(source : "Kennblätter fremden geräts heft 8a, Munition bis 3,6 cm" Released in Berlin 1941)

100 meters = 47mm /0°
500 meters = 40mm /0°
1000 meters = 30mm /0°

100 meters = 35mm /30°
500 meters = 30mm /30°
1000 meters = 20mm /30°

100 meters = 18mm /45°
500 meters = 16mm /45°
1000 meters = 15mm /45°

Regards,

David

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David Lehmann
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#5

Post by David Lehmann » 07 Jun 2005, 01:35

The 37mm infantry gun was also still used sometimes as AT gun in 1940.

Canon de 37mm L/21 Mle1916 TR
This infantry gun was first used during WW1, TR means "Tir Rapide" or "rapid fire". The USA adopted it and it was designated 37mm M1916. However, by 1941 most of them had been put into storage but it was used against the Japanese. The Japanese Type 11 gun was based on this French design. For transport this weapon could be broken down into 3 sections. In addition, wheels could be attached for towing. These guns were sometimes equipped with an armored shield. In German service it was known as the 3.7cm IG 152(f).
1036 of these guns are still in service in 1940 in the French army (mostly in second line infantry divisions) to fulfill the infantry gun and AT gun tasks since there are not enough of the new 25mm AT guns in service in the infantry units. It was very accurate and had a high rate of fire. Each 37mm infantry gun had 120 Mle1916 HE and 80 AP shells available in a French 1940 infantry regiment.
Caliber : 37mm
Crew : 1 NCO + 6 men
Length : 3.50m
Width : 1.05m
Barrel length : 790 mm
Weight in action : 108 kg
Weight in travel : 160 kg (with the wheels)
Protection : the shield is 6.5mm thick
Rate of fire : 15-30 rpm
Traverse : 35°
Elevation : -8° to +17°
Telescopic sight : 2x (L.698 sight, field of view 7.88°, + reticle, adjustable drum up to 1800m)
Muzzle velocity : 367-600 m/s (HE and AP shell)
Max Range : 2400m
Practical range : 400m against light armored vehicles and 1500m against soft targets

Ammunitions : (French penetration data)
Obus de rupture Mle1892/1924 (APHE) - in German service : Pzgr 148(f) -
Caliber : 37x94R mm
Weight of projectile : 0.500 kg (15g explosive)
Length of projectile : 94.5mm
V° = 388 m/s
Penetration : 8mm /30° at 400m

Boulet de rupture Mle1935 (AP/API) - in German service : Pzgr 150(f) -
Caliber : 37x94R mm
Weight of projectile : 0.390 kg
Length of projectile : 88mm
V° = 600 m/s
Penetration : 18mm /35° at 400m

Obus explosif Mle1916 (HE) - in German service : Sprgr 147(f)
Caliber : 37x94R mm
Weight of projectile : 0.555 kg (30g explosive)
Length of projectile : 109.5mm
V° = 367 m/s

Boîte à balles Mle1908 (canister) - in German service : Ktgr 169(f) -
Calibre : 37x94R mm
Weight of projectile : 0.550 kg (28x14.7mm hardened lead balls)
Length of projectile : 110mm

Boîte à balles Mle1918 (canister) - in German service : Ktgr 168(f) -
Calibre : 37x94R mm
Weight of projectile : 0.705 kg
Length of projectile : 110mm

Regards,

David

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#6

Post by David Lehmann » 07 Jun 2005, 01:40

The main problem associated with armor penetration numbers is that of test conditions. Most, if not all, data that is presented in books about the subject list only three values: a thickness, range, and angle. Not that these aren't important, but there are other just as important figures that need to be listed to accurately model the penetration of armored plates : the test conditions.

For a thickness to be penetrated, there must be attached onto it some sort of criteria for determining what is "penetrated". For instance, the numbers presented in Jentz relate to a test criteria of 5 to 10 consecutive full perforations of high quality test plate (in the range of 280 BHN to 320 BHN) using high quality test-proof ammunition. This strict criteria leads to lower numbers where a more relaxed test criteria would lead to higher numbers. Direct comparison of figures from one source testing criteria to another will thus obviously produce only flawed results (hence the large discrepancy in figures between different sources).

To accurately model armor penetration using these numbers from different sources, the usage of multipliers can be used to convert numbers from one criterion to another. Each multiplier adds a level of inaccuracy, but it allows at least some degree of similarity between figures.

The standard notion that is sometimes used is based on the 50% success "half make it, half don't" against standard homogenous test plate (keyed at 240 BHN) using production quality rounds criterion. This criteria is used extensively in works such as that from Bird, and offer a reasonable approach to armor penetration issues since it works itself well into other formulas that Bird has proposed.

Below are tables which detail some common sources and their common test conditions. Appendix B gives a table of proposed multipliers used to convert from different test conditions.

Thomas Jentz (Panzertruppen) :
• Based on original German test conditions
• 5 to 10 consecutive perforations
-- 5 consecutive for 7.5cm and larger
-- 10 consecutive for 3.7cm and smaller
-- 7 is estimated by Bird for rounds in between these two calibres
• Against high quality homogenous test plate
-- Free of defects
-- In 1940-1941, keyed at 280 BHN to 320 BHN
• Using high quality test-proof rounds
-- Which do better than standard production quality rounds by 5 to 10 percent, based on caliber (larger caliber, such as 8.8cm, would be at 5% reduction where as small caliber, such as 2.0cm, would be at 10% reduction, although standard reduction is sometimes said to be roughly 8 to 9 percent for all rounds).

Lorrin Bird (WWII Ballistics) :
• Based on British BIOS reports and multiple other sources
• 50% success, "half make it, half don't"
• Against machineable quality homogenous test plate
-- Free of defects
-- Keyed at 240 BHN
• Using production quality rounds.

French Data (estimation) :
• Based on original French test conditions
• Seems to follow a 100% success rate
• Against an unknown test plate
• Using production quality rounds.


Angle of impact, caliber of round, and thickness of armor plate being attacked all play a vital role in overall armor penetration. The most favorable of these, which can be influence by any one mobile weapon system, is impact angle. The most favorable impact angle is the perfect 0 degree impact angle, in which all energy is directed towards penetration rather than towards ricochet/slope effect. Weapon penetration statistics can only be compared to each other when the figures presented are expressed at 0 degree from vertical mark, otherwise slope effects, which are a function of both thickness of armor and caliber of shell (T/D ratio), cause discrepancies.

The likelihood in normal combat conditions to hit in the 0 to 10 degree impact angle range is usually expressed as less than 10%. The likelihood of the perfect 0 degree shot angle is flat out a near impossibility unless from < 50m. The majority of engagements, prior to maneuver, are usually in the 30 to 60 degree impact angle range.

Sloped and rounded armor adds to the unlikelihood of the 0 degree penetration mark by mathematically allowing only one particular horizontal/vertical section which will produce a 0 degree impact angle.


PENETRATION AT 0° AND AT 100m :

The penetration numbers used as basis for the calculations are the ones based on the tests performed by W.A. Prueff, as found in Panzertruppen (Jentz) since they are real tests in standard German test conditions.

1.27 is the multiplier from 10 consecutive perforations to 50% success rate (test condition conversion). German tests were always based on this stricter scale.

0.9 is the ammunition multiplier from test-proof high quality rounds to production quality rounds for small calibre ammunition (less than or equal to 40mm).

0.7-1 is 30° degree standard slope multiplier from 30° to 0° for 2.0cm ammo
0.75-1 is 30° standard slope multiplier from 30° to 0° for 3.7cm ammunition
etc.

The 30° slope multipliers are from observed values where known penetration is listed for both 30° and 0° for that caliber of weapon.


3.7cm AP KwK/PaK L/45 : (e.g. Pz III F & 3.7cm PaK)
35.0 * 0.75-1 * 1.27 * 0.9 = 53.34 mm @ 100m
29.0 * 0.75-1 * 1.27 * 0.9 = 44.20 mm @ 500m
22.0 * 0.75-1 * 1.27 * 0.9 = 33.53 mm @ 1000m
20.0 * 0.75-1 * 1.27 * 0.9 = 30.48 mm @ 1500m


2.5cm KwK121(f) & Pak112(f) :
35.0 * 0.7-1 * 1.27 * 0.9 = 57.15 mm @ 100m
29.0 * 0.7-1 * 1.27 * 0.9 = 47.35 mm @ 500m
20.0 * 0.7-1 * 1.27 * 0.9 = 32.66 mm @ 1000m
Remember that this is a low calibre and that the T/D ratios encourage ricochet (e.g. bad slope multipliers) - e.g. angled hits reflect smaller calibers much higher than larger ones.

The 0.7-1 is for the 20mm ammunition, it might be a bit off for the 25mm ammunition. The adequate multiplier might more be like 0.72-1 or 0.73-1, resulting in :

35.0 * 0.72-1 * 1.27 * 0.9 = 55.56 mm @ 100m
29.0 * 0.72-1 * 1.27 * 0.9 = 46.03 mm @ 500m
20.0 * 0.72-1 * 1.27 * 0.9 = 31.74 mm @ 1000m
or
35.0 * 0.73-1 * 1.27 * 0.9 = 54.80 mm @ 100m
29.0 * 0.73-1 * 1.27 * 0.9 = 45.40 mm @ 500m
20.0 * 0.73-1 * 1.27 * 0.9 = 31.31 mm @ 1000m

For the French 25mm AT gun the penetration at 100m and for an impact angle of 0° is about 55mm. This gives anyway until 500m a penetration slightly better than for the AP shell of the German 3.7cm PaK / KwK.


4.7cm Pak181(f) :
57.0 * 0.78-1 * 1.25 * 0.915 = 83.58mm @ 100m
50.0 * 0.78-1 * 1.25 * 0.915 = 73.32mm @ 500m
42.0 * 0.78-1 * 1.25 * 0.915 = 61.59mm @ 1000m
36.0 * 0.78-1 * 1.25 * 0.915 = 52.79mm @ 1500m

David

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#7

Post by David Lehmann » 07 Jun 2005, 01:41

According to the German brigade general Kühne :
"The single efficient German gun against the French Renault D2, Somua S35 and Renault B1bis tanks is the 7.5cm KwK L/24 of the Panzer IV - firing an APCBC shell - (and the 8.8cm FlaK which penetrates all the enemy armor up to 2000m).
The shells from our 3.7cm Kwk/PaK L/45 are inefficient against all these tanks at standard range (300-400m) and bounce even at a very favourable impact angle. At close range out 3.7cm gun can nevertheless penetrate the lighter French tanks (35-40mm armor) and the shell penetrates them at an angle of 0° at <300m. The 3.7cm AP shell did not fulfil its mission and is not adapted to warfare against modern tanks.
Direct hits with the 7.5cm HE shell have no effect against the Somua S35 or the Renault B1bis at 600 to 800m.
The 2.0cm AP shell cannot penetrate the French tanks, its single effect is on the morale (personal note : there are several French testimonies of Somua S35 or Hotchkiss tanks being penetrated at point blank range on the side). The British tanks were penetrated at all ranges by the 2.0cm AP shells, except the Matilda II heavy tank, luckily in very small number. The armor of the Matilda II resists even sometimes to our 7.5cm guns.
Huge quantities of ammunition were used during the battles against French tanks because of the lack of power of the 2.0cm and 3.7cm guns. In our brigade, all the 3.7cm and 7.5cm shells were used during a single battle on 13th May. Our unit had to wait for ammunition supply to continue to fight.
The equipment of the German turret is completely efficient and it is superior to the French one. This gives an advantage to the German tanks.
The French 47mm SA35 tank gun proved to be remarkable. This gun penetrates all the German tanks independently from the impact angle up to 800m and sometimes more. Several Somua S35 and Renault B1bis destroyed German tanks at a range of 1000m !
The French 37mm SA18 proved to be inefficient.
The French rate of fire is slower because of the conception of the French turrets.
Concerning the AT guns, the accuracy is good for the 47mm SA37, very good for the 25mm SA34/37 and excellent for the British 40mm. The front hull armor of the Panzer III has been easily penetrated by the excellent French 25mm SA34/37 gun. Trials with booty guns proved that the French 25mm AT gun is superior to the German 3.7cm PaK. This 25mm AT gun is very hard to spot because the flash is invisible (flash hider). The armor of the Panzer III and even more of the Panzer IV is insufficient.
The speed of our tanks proved to be very good. In the future we should maintain a capacity of 30-40 km/h in easy offroad. The French tankers or AT gunners who were captured said all that the speed of our tanks constituted the main difficulty to hit them
."

David

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#8

Post by David Lehmann » 07 Jun 2005, 02:09

Hi,

I have also many photos of German tanks, armored cars etc. destroyed in France in 1940. It is often hard to know exactly what happened, what was the weapon that destroyed it etc. For several photos including the following I know that the tanks were destroyed by 25mm AT guns and 47mm AT guns.

Regards,

David
Attachments
Panzer 35(t) hit and put on fire by a 25mm AT gun (46eGRDI) in Epinal.jpg
Panzer 35(t) hit and put on fire by a 25mm AT gun (46eGRDI) in Epinal.jpg (69.27 KiB) Viewed 28450 times
Panzer IV destroyed in Stonne by a 25mm AT gun from 67eRI.jpg
Panzer IV destroyed in Stonne by a 25mm AT gun from 67eRI.jpg (80.8 KiB) Viewed 28462 times

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#9

Post by David Lehmann » 07 Jun 2005, 02:10

2 other photos :
Attachments
Panzer IV destroyed_10 (French 47mm AT gun).jpg
Panzer IV destroyed_10 (French 47mm AT gun).jpg (68.85 KiB) Viewed 28419 times
Panzer III F destroyed_9.jpg
Panzer III F destroyed_9.jpg (78.58 KiB) Viewed 28447 times

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#10

Post by David Lehmann » 07 Jun 2005, 02:53

Note that the 37mm infantry gun was also capable of firing the

Obus de rupture Mle1937 (AP) - in German service : Pzgr 154(f) -
Caliber : 37x94R mm
Weight of projectile : 0.500 kg
Length of projectile : 81mm
V° = 600 m/s
Penetration : 21mm /35° at 400m

German tests with 3.7cm Pzgr 154(f) (source : Jentz) :
100 meters = 25mm /30°
500 meters = 19mm /30°


But without being 100% sure I think that this shell was more used by French tanks armed with the 37mm SA18 gun than by infantry units with the 37mm infantry gun. Most of the French tanks in 1940 are armed with the poor 37mm SA18 gun.

NUMBER OF FRENCH TANKS IN FRANCE ON 10th MAY 1940, IN COMBAT UNITS : 2307 (2777 with obsolete tanks)
• Hotchkiss H35 : 328
• Hotchkiss H39 : 474
• Renault R35/39 : 900
• FCM36 : 90
• Somua S35 : 264
• Renault D2 : 45
• Renault B1bis : 206
--> Modern tanks : 2307

• Renault FT17 : 462 (obsolete)
• FCM-2C : 8 (obsolete)
--> Obsolete tanks : 470

If the AMR tracked armored cars are counted as light tanks :
• AMR33 / AMR35 ZT1 : 259 (including about 150 AMR35 ZT1)
• AMR35 ZT2 : 10
• AMR35 ZT3 : 10
--> TOTAL : 3056 French tanks

On 10th May 1940, there are 2636 German tanks, 99 Panzerjäger I, 24 Sturmgeschütze, 38 15cm s.I.G.33 auf Pz.Kpfw.I, 6 8.8cm FlaK (Sfl) auf Sd.Kfz. 8 and 917 armored cars for a total of 3720 German AFVs. 965 tanks are armed with a 3.7cm or 7.5cm gun, 99 Panzerjäger I with a 4.7cm gun and 24 StuG III with a 7.5cm gun. That leads to 1088 German AFVs armed with a good AT capacity (not counting the 6 8.8cm self-propelled AT guns).

There are 2307 modern French tanks (2777 tanks with the obsolete FT17 and FCM-2C tanks) and about 575 armored cars or light reconnaissance tanks. That makes 3056 French tanks (if the AMR33/35s are counted as tanks) :
• only about 480 French tanks armed with a 47mm SA35 (including the B1bis tanks with their 75mm hull gun)
• about 300-350 which have a 37mm SA38 gun.
• from the 279 AMR33/35s, 259 are only armed with a single 7.5mm or 13.2mm MG and 20 AMR35 have a 25mm SA35 gun, which is also better than the German 3.7cm gun.
That makes 800-850 French tanks (26-28%) with an excellent to good anti-tank capacity.

The huge majority of the French tanks (2206-2256 tanks) are light tanks armed with the 37mm SA18 gun or only MGs. The 37mm SA18 gun can be used at 300-400m against the Panzer I and Panzer II but to knock out a Panzer III Ausf.E/F (the previous models are less armored and easier to destroy) or a Panzer IV Ausf.C/D, they have to get as close as < 25-100m, whereas the enemy can destroy them at about 300m (3.7cm KwK) to 500m (7.5cm KwK) and even from longer range if you consider the obsolete Renault FT17.

On 10th May 1940, the British armored units add only 23 tanks (Matilda II) with a good AT capacity and the Belgian armored units add 236 tanks and self-propelled AT guns for a total of 1059-1109 allied AFVs with a good to very good AT capacity.

But note that the German AFVs have an armor of 13-30mm whereas the French tanks (except the obsolete ones) have generally a 40-60mm armor (35mm for the hull of the Hotchkiss H35).

There are comparable numbers of allied and German tanks with about 2800-2900 tanks. If all the AFVs are counted there are 4033 allied vs 3720 German AFVs, with the obsolete French FT17 and FCM-2C tanks being counted (3563 allied vs 3720 German AFVs without them). This apparent "equality" in the number of tanks is purely mathematical and just taken as such by many people. In the facts it is completely false.

All the about 3000 German tanks are concentrated in the 10 Panzerdivisionen unlike only about 960 French tanks in the DCR/DLM. Each DCR/DLM has less tanks than a Panzerdivision : there are roughly 10x300 German tanks against 6x160 French tanks and many dispersed battalions. That was the reality on the battlefield. The British 1st AD, which arrives during May 1940, concentrated the cruiser tanks but did not really change the balance and was quickly neutralized. All the Belgian tanks were dispersed in small numbers in their infantry divisions, the higher number of Belgian tanks could be found in the 1e division de chasseurs ardennais with about 50 AFVs. During the battle the Belgian AFvs were generally dispersed in groups of 2-4 AFVs.

In the DLM/DCR 80-90 tanks are only light tanks unlike what was initially planned (only medium/heavy tanks). 80% of these light tanks are armed with the 37mm SA18 L/21 gun and only 20% with the 37mm SA38 L/33 gun. The 37mm SA18 is only adapted to infantry support. A tank armed with the 37mm SA18 gun can actually destroy armored cars, Panzer I and Panzer II tanks at 300-400m but has to go closer than 25-100m to have a chance to destroy a Panzer III or Panzer IV, whereas it can itself be destroyed at 300-400m by them.

The DLMs were led by the cavalry corps HQ and the different DCRs were commanded by an armored group HQ. Nevertheless, these HQs had insufficient means unlike the Panzerkorps which had fully operational HQs.

Thanks to more radio sets the German tanks were able to better coordinate and concentrate their attack, changing more easily the attack axis. The French tanks favored better armor (and armament if we exclude the 37mm SA18 gun) rather than communications and speed. This better tactical regulation resulted in much more concentrated German armor against allied tanks, usually 4 vs 1, sometimes even 8-10 vs 1 odds.

Regards,

David

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#11

Post by Tony Williams » 07 Jun 2005, 09:32

Great stuff as usual David. The photos below, from the Ammo Photo Gallery on my website, show the tank and anti-tank ammo in use in the 1940 battles. How many can you identify without looking up the answers on my website? :)

Tony Williams: Military gun and ammunition website and discussion forum

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#12

Post by David Lehmann » 07 Jun 2005, 11:38

Hello Tony,

Here are several French shells on wartime photos :
Attachments
47mm SA37 (47x380R shells with and without ballistical cap, gas mask and Hotchkiss Mle1914 MG).jpg
47mm SA37 (47x380R shells with and without ballistical cap, gas mask and Hotchkiss Mle1914 MG).jpg (115.6 KiB) Viewed 28249 times
captured Renault UE trailer with 25mm AT gun ammunition (25x194R shells).jpg
captured Renault UE trailer with 25mm AT gun ammunition (25x194R shells).jpg (80.34 KiB) Viewed 28283 times
25mm SA34 AT gun (see the 25x194R shells).jpg
25mm SA34 AT gun (see the 25x194R shells).jpg (94.66 KiB) Viewed 28302 times

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#13

Post by David Lehmann » 07 Jun 2005, 11:40

More :
Attachments
French 60mm Mle1935 mortar shells and Berthier 3-cartridge clip.jpg
French 60mm Mle1935 mortar shells and Berthier 3-cartridge clip.jpg (84.93 KiB) Viewed 28148 times
German Somua S35 and its 47x194R shells.jpg
German Somua S35 and its 47x194R shells.jpg (69.17 KiB) Viewed 28176 times
37x94R shells (37mm SA18 gun) and 150 rounds magazine on a Renault R35.jpg
37x94R shells (37mm SA18 gun) and 150 rounds magazine on a Renault R35.jpg (119.37 KiB) Viewed 28215 times

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#14

Post by Markus Becker » 07 Jun 2005, 11:47

David Lehmann wrote:
A tank armed with the 37mm SA18 gun can actually destroy armored cars, Panzer I and Panzer II tanks at 300-400m but has to go closer than 25-100m to have a chance to destroy a Panzer III or Panzer IV, whereas it can itself be destroyed at 300-400m by them.

David
Three or four of the 10 Armoured Division of the Wehrmacht were equipped with Pz.35(t) and Pz.38(t). IIRC their armour plates were made of lower quality steel that often shattered when hit. How effective are SA18 guns against those tanks?

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#15

Post by David Lehmann » 07 Jun 2005, 12:18

Hello,

Indeed the Panzer 38(t) e.g. in the 7.PzD (Rommel) had the best 3.7cm gun - L/47.8 - on the German side (except when the 3.7cm KwK L/45 firing APCR shells is considered). This gun and the 7.5cm of the Panzer IV and StuG III were the best German tank guns in 1940. The 4.7cm of the Panzerjäger I was the best German AFV gun (if the 6 SP-AT guns with a 8.8cm gun are not counted). But the Panzer 38(t) was less armored than the Panzer III.

A crude estimation of the capabilities (not the max penetration) of the French tank guns given in an intelligence report of the 2e DCR (this is not a ballistics study, it is just to give an estimation of part of the capabilities to inform the crews) gives an advice at which range engage the enemy tanks with good kill probability. Against German medium/heavy tanks :
37mm SA18 --> 100m
37mm SA38 --> 400-600m
47mm SA35 --> 600-800m
75mm SA35 --> 700-800m
Lighter tanks and armored cars could be engaged at longer range.

The 47mm SA35 for example destroyed German tanks up to 1000m.

47mm SA35 L/32 - in German service : 4.7cm KwK 173(f) -
Theoretical rate of fire : 15 rpm (6 rpm in a B1bis turret in accurate aiming, could drop to 2-4 rpm in combat)
Telescopic sight :
• 4x (L.724 sight, field of view 11.25°, V and later + reticle, range drum up to 1500m for the AP shells and 1600m for the coaxial MG) for the APX1 turret
• 4x (L.762 sight, field of view 11.81°, + reticle, range drum up to 1500m for the AP shells and 1600m for the coaxial MG) for the APX4 turret
• There might be a L.731 sight for the APX1 CE turret (Somua S35) but there is no information about it at the moment.
Practical AT range : 800-1000m

Ammunitions :

Obus de rupture Mle1935 (APC) - in German service : Pzgr 176(f) -
Caliber : 47x193R mm
Weight of projectile : 1.620 kg
Length of projectile : 145mm (length of the case : 193mm and total length of the shell : 325mm)
V° = 660 m/s
Penetration : 40mm/30° at 400m

German tests with 4.7cm Pzgr 176(f) (source : Jentz) :
100 meters = 39mm /30°
500 meters = 33mm /30°
1000 meters = 26mm /30°
1500 meters = 20mm /30°
There is no problem to penetrate the German tanks front armor at 800m range, when the hit angle was good enough.

Obus explosif Mle1932 (HE) - in German service : Sprgr 175(f) -
Caliber : 47x193R mm
Weight of projectile : 1.410 kg (142g explosive)
Length of projectile : 183mm
V° = 590 m/s

The 47mm SA35 gun in the APX4 turret :
Accuracy of the 47mm SA35 gun with AP shells :
15 shots at 200m : H+L = 10+20 = 30cm
10 shots at 500m : H+L = 55+53 = 108cm

- Rate of fire in accurate aiming/firing : 6 rpm (the gun by itself has a RoF of 15 rpm). In combat the RoF could drop to 2-4 rpm.
- Stability : gun is very stable but turret can rotate a few degrees to the right because the gun is not centered, therefore there is a turret blocking mechanism.
- Gun repair :
Replacement of firing pin : 2min 4s
Replacement of extractors : 1min 45s


The 75mm SA35 hull gun of the Renault B1bis had roughly the same penetration capacity than the 47mm SA35 mounted in the turret.

75mm SA35 L/17.1 - in German service : 7.5cm KwK 251(f) -
Telescopic sight : two L.710 sights forming prismatic binocular sights (stereoscopic telemeter, each sight with a 3.5x magnification, a field of view of 11.15° and range ladders, adjustable drum up to 1600m for the HE shells and 1560m for the APHE shells)

Ammunitions :
Obus de rupture Mle1910M (APHE)
Caliber : 75x241R mm
Weight of projectile : 6.400 kg (90g explosive)
Length of projectile : 239.5mm
V° = 475 m/s
Penetration : 40mm /30° at 400m (French data)
The APHE shell is intended to detonate once the armor has been penetrated. Because of the necessity for a hard point to APHE shells, the fuze is fitted into the base of the projectile. This fuze acts through inertia. As the shell passes up the barrel, either the shock of firing or the rapid rotation removes a safety device and arms the fuze. This fuze contains roughly a weight held by a spring. When the shell hits something hard, momentum throws the weight forward so it strikes the firing element of the fuze and thereby ignites the HE filler of the APHE shell.

Obus explosif Mle1915 (HE)
Caliber : 75x241R mm
Weight of projectile : 5.550 kg (740g explosive)
V° = 500 m/s
Equipped with the long RYG Mle1921 fuze for better anti-personal efficiency. This long fuze explains probably why there were only 6 armed shells in the B1bis and 6 longer emplacements for them in the ammunition racks.

The 75mm HE shells are able to destroy the armored cars, Panzer I and Panzer II and are very efficient at short range against the tracks and lower parts of the heavier tanks. The HE shell has a penetration of 17mm/30° even at 800m.

Accuracy of the 75mm SA35 gun :
10 shots at 400m : H+L = 30+28 = 58cm



Concerning the 37mm SA18 gun I cannot give a definite answer, it all depends from the shell which is considered (1892/1924 APHE, 1935 AP, 1937 AP), the impact angle etc. But generally and roughly said, all the medium German tanks (Panzer III, Panzer IV, Panzer 35(t) and Panzer 38(t)) had to be engaged at 0-50m if you wanted a good chance to knock them out. If you have 1937 AP shells of course that's far better than the 1892/1924 APHE shell which gives you roughly no chance except lucky hits <25m. The Panzer 35(t) and Panzer 38(t) could probably be engaged up to 100m. You could destroy a Panzer I or a Panzer II at longer range 100-400m.


On the German side in May/June 1940, the only Pzgr.40 (APCR) shells produced were for the 3.7cm L/45 KwK of the PzIII or the 3.7cm PaK which were equipped with a very small number of APCR shells during the battle of France, probably even only to several Panzer III. The 4.7cm Pak(t) (on the Panzerjäger I mainly) received the APCR shell only in July 1940. The Pz35(t) and Pz38(t) did not have an APCR shell until the Russian campaign started. The 2.0cm Pzgr.40 was introduced in December 1940 or the first months of 1941, the other Pzgr.40 types also until May 1941.
The 7.5cm L/24 KwK37 of the PzIV Ausf.A/B/C/D or the StuG III Ausf.A in France in May/June 1940 could fire the K.Gr.rotPz. (AP) at 385m/s (penetration of 41mm/30° at 100m) but also a HEAT shell (Gr.38 HL/1) at 452m/s which was available in very small numbers but allowed a penetration of 45mm/30° at any range. There was no HEAT shell ready for the campaign in Poland. The Gr.38 HL/1 made the final tests in December 1939 and the shooting of the ballistic tables was finished in March 1940. The shells is listed in the ammo manual of the 7.5 cm KwK from July 1940. HEAT shells use chemical penetration instead of kinetic penetration thus the same amount of armor penetration could be achieved despite striking velocity. HEAT shells also tended to do better with striking armor plates at an angle, but were also easily defeated by employing spaced armor (like the armor protecting the wheels on the Somua S35) or side skirting. HEAT shells could also be used as a substitute for HE shells. HEAT shells in early WW2 Panzers were not strong enough to penetrate the stronger French tanks, however later revisions (Gr.38 HL/A, HL/B, HL/C) proved more successful on the eastern front.

If we exclude the direct artillery fire and the 8.8cm L/56 Flak, the 4.7cm Pak36(t) L/43.4 mounted on the Panzerjäger I seems to be the most dangerous gun for the French tanks (except the HEAT shell of the 75mm L/24 beyond 500m). The French 47mm L/53 AT gun is the best AT gun before the 5.0cm Pak38 and 7.5cm Pak40. On the French side, the Laffly W15 TCC (tank destroyer) was really gast and deadly against German tanks with its 47mm L/53 and the Mle1936 APCBC shells.

The best French tank gun is the 47mm SA35 L/32 which is superior to the German tank guns. The best German tank guns are the 3.7cm L/47.8 (t) of the Panzer 38(t) and the 7.5cm L/24 KwK37 of the PzIV Ausf.A/B/C/D or the StuG III Ausf.A. The French 47mm SA35 gun is better than the German 3.7cm guns with AP shells but it is outclassed by the APCR shells of the 3.7cm L/45 at close range and by the 7.5cm L/24 gun at medium/long range with its HEAT shells. The APCR shells of the 3.7cm L/45 gun are able to penetrate the front armor of a Renault B1bis tank at 100m. The 47mm SA35 L/32 gun APC shells are slower than the AP shells of the 3.7cm L/45 gun (660 versus 745 m/s) but much heavier (1.620 kg versus 0.685 kg) and capped. The French 47mm has a higher KE and a better T/D ratio, leading to a better penetration.

-------

Concerning the Renault B1bis "invincibility" :

Penetration from the front is minimized due to the frontal sloped armor, penetration on the turret is minimized due to rounded construction and the armor thickness in 60mm RHA on the front hull and 56mm cast on the turret (+ the gun mantlet on the front turret).

The 3.7cm PaK earned it's nickname of "door knocker" when faced against the British Matilda II tanks (only 23 in the 1940 western campaign) and/or the Renault B1bis tanks, the last one being called "Kolossus".

Concerning the usage of German APCR rounds (Pzgr.40) available in small number for the PzKpfw III F and 3.7cm PaK in June 1940, the round is VERY light. After 250m, the APCR round looses its amount of overall energy at an incredible rate. After about 300m, standard AP shot will do more than APCR will be able to do. From 0-250m though, even the Renault B1bis and Matilda II are both at risk if a good shot from an APCR round is attained. Under 250m range from favourable angles, the B1bis is easily susceptible to penetration by the 3.7cm APCR round fired from the PzKpfw III F, especially in the side and rear hull which are vertical plates.

At most combat ranges from favorable angles, the B1bis is susceptible to penetration by the 4.7cm Pak(t) auf PzKpfw I Ausf B (PanzerJäger I Ausf. B), especially in the side and rear hull which are vertical plates.

The B1 bis, in most regards, is "invincible" to most rounds otherwise from all German calibers, including 7.5cm shells fired from the PzKpfw IV and StuG III. At close range (< 100m) the 7.5cm shells are a threat but not the 3.7cm AP shells which are not sufficient.

The Renault B1bis, in most combat conditions is a very dangerous opponent. Once it looses it's ability to maneuver (e.g. track knocked off) or when outnumbered and loosing tactical awareness, it is a sitting duck for a skilled commander (with the help of smoke rounds also for example).

On 16th May in Stonne, a single B1bis tank (the B1bis "Eure" from Lieutenant Bilotte) pushed in the town itself into the German defenses and went back. He attacked a German column of Pz.Rgt.8 and destroyed 2 PzIV, 11 PzIII and 2 PaK36 guns. The first shots destroyed simultaneously the first (with the 47mm gun) and the last tank (with the 75mm gun) of the column. The first German tanks were at less than 50m range. The armor of the B1bis was scattered with 140 impacts, no one penetrated or really damaged the armor.

During the battle of Abbeville the B1bis "Jeanne d'Arc") sustained more than 90 impacts from 3.7cm PaK without being penetrated and simply crushed several AT guns.

The B1bis was almost invincible when engaged by 3.7cm AT guns if not a point-blank range and a lot of luck. Mostly all the B1bis that had been lost due to the enemy had been destroyed by 8.8cm Flak, indirect artillery fire, direct 10.5cm artillery fire and anti-tank mines. Many others have been abandoned after mechanical breakdowns or being out of fuel.

Regards,

David

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