M3 howitzer

M3 105 mm Howitzer
A M3 Howitzer outside the Army Museum in Honolulu, Hawaii.
Type	Light Howitzer
Place of origin	United States
Service history
In service	1943 - ?
Used by	United States
Wars	Second World War
Production history
Designed	1941
Produced	1943-45
Number built	2,580
Specifications
Weight	2,495 lb (1,130 kg)
Length	155 inches (3.94 m)
Barrel length	bore: 1.68 m / 16 calibers overall: 1.88 m / 17.9 calibers
Width	67.5 inches (1.70 m)
Height	49.75 inches (1.26 m)
Shell	105x372R
Caliber	105 mm
Breech	Horizontal block
Recoil	Hydropneumatic, constant
Carriage	split trail
Elevation	-9° to 30°
Traverse	45°
Rate of fire	4 rounds per minute burst 2 rounds per minute sustained
Muzzle velocity	1,020 ft/s (311 m/s)
Maximum range	HE: 8,300 yards (7,600 m)

The 105 mm Howitzer M3 was a US light howitzer designed for use by airborne troops. The gun utilized a barrel of the 105 mm Howitzer M2, shortened by 27 inches and fitted to a slightly modified split trail carriage of the 75 mm pack howitzer. The howitzer was used by US Army during the Second World War. It was issued to airborne units and to cannon companies of infantry regiments.

Contents 1 Development and production 2 Service 3 Variants 4 Self-propelled mounts 5 Ammunition 6 Notes 7 References

Development and production

The process of building airborne forces led in 1941 to a requirement for an air portable 105 mm howitzer. The weapon, initially designated T7, featured a barrel of 105mm Howitzer M2, shortened by 27 inches (68.6 cm) and combined with recoil system and carriage of the 75 mm field howitzer. A prototype reached trials at Aberdeen Proving Ground in March 1942.^[1] The howitzer was designed to fire the same ammunition as the longer M2. It turned out, however, that shorter barrel resulted in incomplete burning of the propelling charge. The problem could be solved by use of faster burning powder. Otherwise the design was considered acceptable and was standardized as 105mm Howitzer M3 on Carriage M3. The carriage was soon succeeded by M3A1, which had trails made from thicker plate. Even stronger tubular trails were designed, but never reached production.^[1] The production started in February 1943 and continued until May 1944; an additional bunch was produced in April-June 1945.^[1]

Production of М3, pcs.[2]
Year	1943	1944	1945	Total
Produced, pcs.	1,965	410	205	2,580

Service

M3 howitzers were employed by glider artillery battalions of airborne divisions. Jeep was used as prime mover. They were also issued to cannon companies of infantry regiments - six in three platoons of two. Infantry typically used 1 1/2 ton truck as prime mover.^[1] A small number of M3 were supplied via lend lease channels: France (94), United Kingdom (2), countries of Latin America (18).^[3]

Variants

Gun variants:

• T7, standardized as M3.^[1]
• T10 - variant with elevation improved to 65 degrees.^[1]

Carriage variants:

• M3 - based on M3A1 carriage for the 75 mm field howitzer.^[1]
• M3A1 - had stronger trails, made from 1/8 inch plate instead of 3/32 inch.^[1]
• M3A2 - was fitted with shield.^[1]

Self-propelled mounts

• 105 mm Howitzer Motor Carriage T38 - based on the M3 halftrack, never built.^[4]
• 105 mm Howitzer Motor Carriage T82, in mount M3A1 - based on the Light Tank M5A1 chassis, two pilots built, cancelled in 1945.^[5]

Ammunition

The gun fired semi-fixed ammunition, similar to the ammunition of the M2; it used the same projectiles and the same 105 mm Cartridge Case M14, but with different propelling charge. The latter used faster burning powder to avoid incomplete burning; it consisted of base charge and four increments, forming five charges from 1 (the smallest) to 5 (the largest). Firing M1 HE rounds prepared for the M2 was authorized in an emergency, but only with charges from 1 to 3. M1 HE rounds for the M3 could be fired from M2 with any charge.^[6] HEAT M67 Shell had non-adjustable propelling charge. For blank ammunition, a shorter Cartridge Case M15 with black powder charge was used.^[6]

Available ammunition[6][7][8]
Type	Model	Weight, kg (round/projectile)	Filler	Muzzle velocity, m/s	Range, m
HE	HE M1 Shell	18.35 / 14.97	TNT or 50/50 amatol, 2.18 kg	311	7,585
HEAT-T	HEAT M67 Shell	16.62 / 13.25		311	7,760
Smoke	WP M60 Shell	18.97 / 15.56	White Phosphorus, 1.84 kg	311	7,585
Smoke	FS M60 Shell	19.65 /	Sulfur trioxide in Chlorosulfonic acid, 2.09 kg
Smoke	HC BE M84 Shell	18.29 / 14.91	Zinc chloride	311	7,585
Drill	Drill Cartridge M14			-	-
Blank				-	-

 

Armor penetration, mm[8]
Ammunition \ Distance, m	0	457	914	1,828
HEAT M67 Shell (meet angle 0°)	102
Concrete penetration, mm[8]
HE M1 Shell (meet angle 0°)	305	274	244	213
Different methods of measurement were used in different countries / periods. Therefore, direct comparison is often impossible.

Notes

1. ^ ^{a b c d e f g h i} Zaloga - US Field Artillery of World War II, p 13-14.
2. ^ Zaloga - US Field Artillery of World War II, p 9.
3. ^ Zaloga - US Field Artillery of World War II, p 37.
4. ^ Hunnicutt - Half-Track: A History of American Semi-Tracked Vehicles, p 121.
5. ^ Hunnicutt - Stuart: A History of the American Light Tank, p 332-333, 504.
6. ^ ^{a b c} Technical Manual TM 9-1901, Artillery Ammunition, p 167-178
7. ^ Technical Manual TM 9-1904, Ammunition Inspection Guide, p 471-484.
8. ^ ^{a b c} Hunnicutt - Stuart: A History of the American Light Tank, p 504.

References

• Hunnicutt, R. P. (1992). Stuart: A History of the American Light Tank.. Presidio Press. ISBN 0-89141-462-2. 
• Hunnicutt, R. P. (2001). Half-Track: A History of American Semi-Tracked Vehicles. Presidio Press. ISBN 0-89141-742-7. 
• Zaloga, Steven J. (2007). US Field Artillery of World War II, illustrated by Brian Delf, New Vanguard 131, Osprey Publishing. ISBN 978-1-84603-061-1. 
• Technical Manual TM 9-1326, 105 mm Howitzer M3 and Howitzer Carriages M3 and M3A1. War Department, 1944. 
• Technical Manual TM 9-1901, Artillery Ammunition. War Department, 1944. 
• Technical Manual TM 9-1904, Ammunition Inspection Guide. War Department, 1944. 

United States artillery of World War II

Tank guns 37 mm gun M5/M6 | 75 mm gun M2/M3/M6 | 76 mm gun M1 3 inch gun M7 | 90 mm gun M3 | 105 mm howitzer M4 Anti-Tank guns 37 mm M3 | 57 mm M1 | 75 mm M1897 | 3 inch M5 | 90 mm T8 Field, Medium and Heavy guns 75 mm howitzer M1 | 105 mm howitzer M2 | 105 mm howitzer M3 4.5 inch gun M1 | 155 mm howitzer M1918 | 155 mm howitzer M1 155 mm gun M1918M1 | 155 mm gun M1/M2 "Long Tom" | 8 inch howitzer M1/M2 8 inch gun M1 | 240 mm howitzer M1 Other vehicle mounted 75 mm howitzer M2/M3 | 75 mm gun M1897 | 105 mm howitzer M2 155 mm gun M1918MI | 155 mm gun M2 Anti-aircraft guns 37 mm M1 | 40 mm M1 | 3 inch M3 | 90 mm M1 | 120 mm M1