# Sd. Kfz. 11 based SP AT guns.



## davebender (May 31, 2012)

le. Zgkw. 3t
1935. 1 Prototype. HL.kl.3 (H). 3.7cm main gun in rotating turret.
1936. 1 Prototype. Hl.kl.4 (H). 7.5cm main gun in rotating turret.
1937 to 1939. 30 prototypes. Hanomag H8 (H). 
.....Engine moved to rear for all 3 prototypes.
.....11mm to 20mm armor.






Why didn't the German Army complete development and put these or similiar Sd.Kfz.11 chassis tracked fighting vehicles into mass production? More powerful and less expensive then the Panzer II ausf C. Suspension is better too. Or you could go a size larger by using the Sd. Kfz. 7 chassis which was fully developed and in mass production during 1937.


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## Denniss (Jun 1, 2012)

Chassis underpowered/overloaded with the long 7.5 cm gun, high silhouette and low armor.


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## davebender (Jun 1, 2012)

You are probably right. However the 5cm/42 cannon might be a good fit. Or perhaps the new 3cm Mk101 autocannon. With 30mm angled armor such a vehicle could be effective prior to 1942. It would certainly be a tougher opponent then the Panzer II yet no more expensive to produce.

Apparently two of the Hanomag H8 (H) prototypes (7.5cm/40.8 cannon) made it to North Africa. Rommel put them to good use as tank destroyers. Fully rotating turret. However I don't think you want to fire a 7.5cm high velocity cannon on such a light vehicle with the turret turned sideways.





After moving the engine to the rear I think Hanomag should have eliminated the front tires by lengthening the track. That would have completed transformation from 3/4 track APC to full track light tank.


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## Denniss (Jun 1, 2012)

May also be a unit conversion - only six roadwheels and turret does not look moveable.


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## davebender (Jun 1, 2012)

As one would expect, prototypes were each a bit different. However the rotating turret is obvious in the top photograph.
7.5cm Selbstfahrlafette L/40.8
*Model I* (with 7.5cm/40.8 cannon)






*Model II* (with 7.5cm/40.8 cannon)






*Wikipedia data for Pz.Sfl. II*
Pz.Sfl. II - Wikipedia, the free encyclopedia


> Development began in 1936 when Büssing-NAG was given a contract to develop an advanced half-track chassis with a rear-mounted engine specifically designed for use as a tank destroyer. Four prototypes of the HKP 902 chassis, No. 9009-2012, were built, two of which had Rheinmetall-Borsig's 7.5 centimetres (3.0 in) L/40.8 gun mounted in an open-topped, low-profile turret.
> 
> The gun could depress 8° and elevate 20°. It fired a 6.8 kilograms (15 lb) K.Gr. rot Pz. (APCBC) shell with a muzzle velocity of 685 metres per second (2,250 ft/s) and a 5.85 kilograms (12.9 lb) Sprenggranate (HE) shell at 485 metres per second (1,590 ft/s). It carried 35 rounds on board. The armor protection, designed to be proof against armor-piercing 7.92 millimetres (0.312 in) bullets, was 20 millimetres (0.79 in) thick on the vehicle front, 14.5 millimetres (0.57 in) and 10 millimetres (0.39 in) on the sides, 10 millimetres (0.39 in) on the rear, 10.5 millimetres (0.41 in) on the superstructure roof and 5.5 millimetres (0.22 in) on the belly[1].
> 
> The two prototypes were completed in 1941 and they were organized into a platoon for troop trials with Panzerjäger-Abteilung (Anti-Tank Battalion) 605 of the Afrika Korps. The first vehicle was reported received on 17 January 1942 by Panzerjäger-Abteilung 605, but the second wasn't reported as arrived in Tripoli until 23 February 1942. The platoon was transferred to the Kampfstaffel des Oberbefehlshaber Panzerarmee Afrika (Rommel's personal battle group) on 8 March 1942. Only one vehicle was reported operational on 25 May at the start of Operation Venezia; the other had been captured by the British, as documented by undated photographs. Shortly afterwards, on 5 June, the Kampfstaffel reported that the other vehicle had been lost after knocking out three tanks.



Unfortunately I am unable to find data or a historical photograph for the 30 Hanomag H8 (H) prototypes. Unless my earlier photograph is the H8 and Wikipedia is wrong.


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## davebender (Jun 2, 2012)

Sd.Kfz.6. 5 ton towing capacity.
Sd.Kfz.11. 3 ton towing capacity.
.....Both vehicles in production during the mid 1930s. Both well liked.
.....Sd.Kfz.6 production cancelled during WWII after Heer decided they didn't need a 5 ton tractor.
.....Sd.Kfz.251 APC is based on the Sd.Kfz.11 towing tractor chassis.
Sd.Kfz.7. 8 ton towing capacity.
.....About 12,000 produced.
.....Highly regarded vehicle. Italy produced a copy. Britain also considered copying the Sd.Kfz.7.
.....Sometimes employed as mobile flak vehicle. However I am unaware of any armored SP guns.

Hl.kl3 (H) 3.7cm SP gun was built on the 3 ton Sd.Kfz.11 chassis.
Hl.kl.4 (H) 7.5cm SP gun was built on the 3 ton Sd.Kfz.11 chassis.
30 x Hanomag H8(H) SP guns were built on the 3 ton Sd.Kfz.11 chassis.
.....What happened to these? Some must have been used for combat.

3 x BN10H SP gun were built on the 5 ton Sd.Kfz.6 chassis.
4 x HKp902 SP gun were built on the 5 ton Sd.Kfz.6 chassis.
.....I believe two of these were the vehicles sent to North Africa.


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## davebender (Jun 3, 2012)

Historically the Stummel didn't enter mass production until October 1942. However the vehicle required no new technology. In theory it could enter mass production concurrent with the Hanomag H.kl.6 (i.e. Hanomag version of Sd.Kfz.11 towing tractor) during 1938.

German Hanomag Stummel Photos - Walkaround Gallery






7.5cm/24 main gun plus coaxial MG. Simple mount and gun shield. Open top.
Weapon mount can pivot 12 degrees right or left of center.
52 main gun rounds plus 2,010 rounds of 7.92mm MG ammo.
Spacious interior. Infantry fire team or MG crew often carried in vehicle rear.
Same armor as other Sd.Kfz.251. 6mm to 14.5mm. Nicely sloped.
~30,000 RM.
.....22,000 RM for Sd.Kfz.251 APC.
.....8,000 RM for 7.5cm/24 cannon.

I think this dirt cheap armored fighting vehicle would have been competative during the first half of WWII. Far superior to the Panzer I training tank which was pressed into operational service for lack of a replacement. Probably more useful then the 10 ton Panzer II also.


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## tomo pauk (Jun 4, 2012)

Pre-BMP-3?


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## davebender (Jun 4, 2012)

That's one way to look at it. However if Germany builds vehicles similiar to the Sd.Kfz.251/9 during the mid to late 1930s their purpose would be entirely different.

The new Marxist French government was chomping at the bit to invade. Germany had no tanks prior to 1937 (Panzer I doesn't count) and the Panzer II which entered production during 1937 for 50,000 RM each was weak and rather crude.

Germany had a significant 3/4 track program from 1933 onward. By 1936 they had Sd.Kfz.11 3/4 tracks in mass production (505 produced 1936 -1938 @ 20,000 RM each). For significantly less then the price of a Panzer II you get a vehicle with similiar armor, superior suspension and it can carry a more powerful weapon. So if you need armored fighting vehicles ASAP to deter invasion I think a 3/4 track vehicle would give Germany the most bang for the buck. 

When Germany eventually gets Panzer III MBT into mass production the existing Sd.Kfz.251/9 are easy to convert back to normal APCs. Unlike the Panzer II which required extensive work to convert it into a Wespe SP howitzer or Marder SP AT gun.


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## tyrodtom (Jun 4, 2012)

davebender said:


> The new Marxist French government was chomping at the bit to invade. Germany had no tanks prior to 1937 (Panzer I doesn't count) and the Panzer II which entered production during 1937 for 50,000 RM each was weak and rather crude.


Are you trying to take siegfried's place, while he's in the penalty box.


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## Shortround6 (Jun 4, 2012)

Found this on Wiki while researching for all those french tanks posed to invade Germany in 1935-37. A rather interesting look at both French finances ( and the Germans were playing similar games) and the cost accounting that can go into some armored vehicle prices. 

"The 190,000 FF price (for the complete hull only: the turret added another 100,000), despite being very low when compared in dollars to other tanks of the epoch, is comparable to many similar prices in other French tank contracts. In 1935 there had been for many years a strong deflation of the dollar, making it very strong against the franc. In addition, this was from 1936 worsened by a deliberate French policy of devaluation ([1]) until the FF was fixed against the dollar on 9 September 1939 at a 43.8 to 1 rate. These exchange rates did not reflect internal value though: they were an artificial instrument to stimulate French exports. This explains how the French were able to produce the entire R 35 at about 500,000 FF in 1939: the real value of the materials and labour used, was about $30,000, not $12,000, as the franc was undervalued about 2.5 times. The export price was realistic though and did not reflect the lower prices for raw materials France was able to obtain from its colonies."

the difference between the 190,000 francs for the hull + 100,000 francs for the turret and the 500,000 franc price is accounted for in the fact that the hull and turret price do not include either armament or engine. 

Mr Bender might also want to consider that the MK II tank was proof against 7.7-8mm armor piercing bullets at all ranges and striking angles. The Sd Kfz 250 series was not. The sides and rear were vulnerable at certain ranges and striking angles. 
He may also have a rather exaggerated idea of the Half tracks obstacle ability.


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## davebender (Jun 5, 2012)

The Marxist "Popular Front" French government nationalized the aircraft industry and tank industry. After that none of the official French aircraft and tank prices are likely to be accurate.

Most German weapons production remained in private hands so I see no reason to doubt published weapon costs.


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## Shortround6 (Jun 5, 2012)

Except the German Government was playing the same game with artificial fixing of the Mark vs other currencies to encourage exports and discourage imports. It also shows that you have to read the accounts carefully in order to get good comparisons even in the same country. Cost per vehicle can also vary with the inverse of the number of vehicles in the production run.


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