Germany's 15 cm siG33

Photos

15 cm siG33 (Sf) auf PzKpfw I:	15 cm siG33 (Sf) auf PzKpfw I:	15 cm siG33 (Sf) auf PzKpfw I Ausf B with 10th Panzer Division:
15 cm siG33 auf Fahrgestell PzKpfw II (SF):	15 cm siG33 auf Fahrgestell PzKpfw II (SF):
Sturminfanteriegeschütz 33B: Bundesarchiv, Koblenz

Design

To get more artillery to be self propelled chassis from light and medium tanks were converted to carry a 15 cm infantry gun.

Prototype

Production

• 15 cm siG33 (Sf) auf PzKpfw I Ausf B: 38^1,2
  • Production: 1940¹
  • Manufacturer: Alkett²
• 15 cm siG33 auf Fahrgestell PzKpfw II (SF): 12²
  • Production: November 1941 - December 1941²
  • Manufacturer: Maschinenfabrik Augsburg - Nurmberg⁴
• Sturminfanteriegeschütz 33B:
  • Production: December 1941 - October 1942²
  • Manufacturer: Alkett²

Variants

• 15 cm siG33 (Sf) auf PzKpfw I Ausf B: Alkett converted 38 PzKpfw I Ausf B in mid 1939.⁵ Had entire carriage and wheels of 150 mm howitzer mounted. Had shield to partially protect crew.
• 15 cm siG33 auf Fahrgestell PzKpfw II (SF): Used a modified PzKpfw II chassis. It was widened and lengthened and an additional wheel was added. Range of 4,700 meters. The 150 mm gun could fire a 36.8 lb HE shell at a muzzle velocity of 790'/sec.⁴
• Sturminfanteriegeschütz 33B, 15 cm s.I.G. 33 on PzKpfw III⁶: Made from PzKpfw III chassis.

Usage

15 cm siG33 (Sf) auf PzKpfw I Ausf B

Used in Poland, France in 1940, and in Russia. Equipped sIG Kompanien (heavy infantry gun companies) 701-706 and were used in Belgium, Holland, and France in 1940. The last ones in service were with the 704th schwere Infanteriegeschütz Abteilung of the 5th Panzer Division in Russia in mid-1943.

15 cm siG33 auf Fahrgestell PzKpfw II (SF)

All were shipped to North Africa in 1942 to the 707 and 708 sIG Kp (SF) (heavy infantry gun companies). Took part in the Gazala spring offensive.

Specifications

	15 cm siG33 (SF) auf PzKpfw I Ausf B	15 cm siG33 auf Fahrgestell PzKpfw II (SF)	siG 33B
Crew	41,2,3	42, 54	52
Radio		FuG Spr f2	FuG Spr d2
Physical Characteristics
Weight	19,040 lb, 18,739 lb, 25,353 lb3 8,500 kg1, 11,500 kg3 8.35 tons1, 8.5 tons2,5	25,088 lb, 24,692 lb 11.2 tons2, 12 tons4	21 tons2
Length w/gun	14' 6", 15' 8.75", 15' 3.8"1, 15' 10.4"3 4.67 m1,2, 4.835 m3	15' 2.75"4, 17' 9", 18' 5.41 m2	5.4 m2
Length w/o gun
Height	7' 10.5"3, 8' 4.5", 9' 2", 9' 2.2"1, 2.4 m3, 3.35 m, 2.8 m1,2	5' 3"4, 6' 2.75", 6' 4" 1.9 m2	2.3 m2
Width	6' 9"1, 7' 10.5"3 2.06 m1,2, 2.4 m3	7' 4"4, 8' 6", 8' 8" 2.6 m2	2.9 m2
Width over tracks
Ground clearance		13"4
Ground contact length		94"4
Ground pressure
Turret ring diameter
Armament
Main	150 mm sIG33 L/112 150 mm1 150 mm Howitzer3	150 mm sIG33 L/11 150 mm sIG33 L/122 150 mm Gun Model 19334	150 mm Stu I G L/112
Secondary
MG			7.92 mm MG342
Side arms
Quantity
Main	25	302	302
Secondary
MG			6002
Side arms
Armor Thickness (mm)	131
Hull Front, Upper	13@22°2	0.6"@0°4, 30@9°2	80@10°2 Mantlet: 30@10°2
Hull Front, Lower	13@27°2	30@15°2	30+50 or 50@21°2
Hull Sides, Upper	13@22°2	0.6"@0°4, 15@30°2	50@25°2
Hull Sides, Lower	13@0°2	15@0°2	30@0°2
Hull Rear	13@0°2 & 13@19°2	0.6"@0°4, 15@10°2 & 15@15°2	15@0°2 & 30 or 50@10°2
Hull Top	6@83-90°2 & 6@90°2	5@90°2	10@90°2 + 17@11-90°2
Hull Bottom	6@90°	5@90°2	16@90°2
Turret Front	10@0-25°2	15@10°2
Turret Sides	10@0°2	15@30°2
Turret Rear	open2	open2
Turret Top	open2	open2
Engine (Make / Model)	Maybach NL38TR1,2 Praga3	Maybach HL 62 TRM2 Maybach HL62 TR4	Maybach HL120TRM2
Bore / stroke
Cooling		Water4
Cylinders	63	64
Capacity
Net HP	1503	1404
Power to weight ratio
Compression ratio
Transmission (Type)	5 forward, 1 reverse.2	Synchromesh4 6 forward, 1 reverse2,4	6 forward, 1 reverse.2
Steering		Clutch brake4
Steering ratio
Starter
Electrical system
Ignition
Fuel (Type)		Gasoline4
Octane
Quantity		52 gallons4
Road consumption
Cross country consumption
Performance
Traverse	12.5° left, 12.5° right2, hand2	25°, 10°, hand2	3° left, 3° right2
Speed - Road	21.75 mph3, 24.9 mph1 35 kph3, 40 kph1,2	30 mph4 40 kph2	20 kph2
Speed - Cross Country
Range - Road	87 miles1, 115 miles3 140 km1,2, 185 km3	120 miles4 160 km2	110 km2
Range - Cross Country
Turning radius
Elevation limits	-4° to +75°2	+50°, -0° to +73°4	-3° to +25°2
Fording depth	3'3 0.914 m3	3'4
Trench crossing		6'4
Vertical obstacle		1' 6"4
Climbing ability		35° slope4
Suspension (Type)		Independent leaf spring4
Wheels each side		5 bogie wheels4, 6
Return rollers each side		44
Tracks (Type)		Steel, skeleton type with floating pin4
Length
Width		11 1/8"4
Diameter
Number of links		1054
Pitch		3 5/8"4
Tire tread
Track centers/tread		74"4