US M4A1

- U.S. M4A1 Mortar Motor Carriage -

World War II

The Kit:

This is the 1/72nd scale kit from Hasegawa of Japan. Hasegawa a number of years ago produced a dozen or so armor kits however, the company is better known for their line of scale model aircraft subjects.

This model kit is very basic. Interior detail being basically non-existent... only the seats, steering wheel and dash board being included. It is molded in light grey styrene plastic with the exception of the soft black vinyl used for the tracks. Assembly and fit were sufficient with the parts being rather thick for this scale as can be expected. I had difficulty with track/wheel alignment and the tension of the track broke off the drive and idler wheels. I installed brass rod 'axles' into corresponding holes drilled with a pin vise for added strength. Exterior detail was good or at least present. Profile accuracy was not checked but it does look to be reasonable.

The decals being shown were provided in the kit with the exception of the white aligning stripe on the mortar tube. Kit decals were a little thick with some excess carrier film but were well printed. (A light sanding with very fine sandpaper removed the slight yellowing from aging.) They were applied to the model over a spray coating of Future Floor Wax. Decals reacted well to a couple of thin applications of Solvaset setting solution and once this had thoroughly dried, another thin coating of Future Floor Wax was applied by airbrush.

The windshield was not provided with the kit. It is two-part and was cut to size from clear styrene. It is fixed into place with a couple of drops of Microscale "Kristal Kleer".

The Details and The Extras:
Due to the sparseness of the interior details, most of what is lacking had to be scratch built. The following photos of the unpainted model will show the details that were added. Basically, anything not gray (and black tracks) was outside of the kit contents. Not my best effort by far and I really struggled with building this model. (Some minor additions and deletions have occurred between the assembly and final painting.)

The tarps on the front fenders and the powered winch cover were fashioned from QuikPlastic two-part epoxy. I used drafting tape for the straps and bits of styrene for the 'buckles'. Other items came from my spare parts drawer and some are from ROCO Minitank items in 1/87th scale. They seemed to fit in ok with this 1/72nd scale kit. Still far from accurate but far better than what was provided in the kit.

	The mortar was bare in detail as well and some added work was required. Styrene tubing (drilled out) was used for the barrel clamp with fine wire for the clamp lock and elevation handles. Twisted sewing thread super-glued into place was used to represent the spreader chain.
	I replaced the Machine Gun's barrel with a .50 caliber barrel from ROCO Minitanks.
	The figure being shown was rather poor and he is part of the crew provided with the kit. His helmet appears to be on backwards. Markings on his helmet were hand painted. Five other crew members in sitting poses including the driver were provided in the kit, but these were deemed to be unusable and discarded.

Painting, Weathering and Finishing:

Acrylic paints were used entirely to paint this subject. A wash of Winsor and Newton Oils thinned with Loew-Cornell Odorless Brush Cleaner and Thinner was applied for depth prior to the drybrushing to bring out the highlights. A final coat of acrylic flat was applied to seal the painting.

Microscale "Kristal Kleer" was applied to the headlights, taillights and dash board gages for the 'glass'.


General Vehicle Info:
Manufactured by the White Motor Co., the M4A1, a derivative of the M2 Half-Track Personnel Carrier, entered US Army service in May of 1943 with 600 vehicles being accepted into service. The M4A1 had improved suspension and had a higher combat weight over the M4 MMC. It was the first US Half-Track Mortar Carrier designed to allow for sustained main weapon firing from within the vehicle although, as delivered, the mortar still pointed towards the rear of the vehicle. The M4A1 provided for greater main weapon traversing, 600 mils vs. 130 mils. It was fitted with a front bumper winch which enabled it to self-extract itself. It served throughout World War II mostly (if not entirely) in the European Theatre of Operations. Had the numbers of M4 and M4A1 diminished sufficiently prior to the end of hostilities, it would have most likely been replaced by the M21 MMC. (When 10th Armored Division arrived in theatre in 1944, it arrived with several of the forward-firing M21 MMC.) Assigned to Battalion Headquarters Companies in tank and armored infantry battalions, each company had a platoon of three mortar carriers and a command halftrack. The total vehicle compliment could range between 18 to 27 vehicles per armored division. The M4A1 had a crew of six.

Actual Vehicle Data:
DIMENSIONS, WEIGHTS and PERFORMANCE:
COMBAT WEIGHT	HEIGHT	LENGTH (with Winch)	WIDTH	GROUND CLEARANCE
18,000lbs	89.375in	243.625in	77.25in	11.2in
8,200kg	227.01cm	618.808cm	196.2cm	28.4cm

ROAD SPEED (Maximum)	VERTICAL OBSTACLE (Maximum)	TURNING DIAMETER (Minimum)	FORDING DEPTH (Maximum)	CRUISING RANGE (Approximately)
45mph	12in	59ft	32in	200mi, Road
72kph	30cm	18m	81cm	320km, Road

PRIMARY ARMAMENT:
TYPE	MOUNT	AMMUNITION CAPACITY	TRAVERSE	ELEVATION
81mm Mortar M1	Mount, M1	96 rounds	600 mils	+80° to +40° (Manual)
For Mortar data, go here...
	SECONDARY ARMAMENT:
.50cal M2HB Machine Gun	Flexible on Skate Rail	400 rounds	360° (Manual)	Manual
...or...
.30cal M1919A4 Machine Gun	Flexible on Skate Rail	2000 rounds	360° (Manual)	Manual

AUTOMOTIVE:
Engine	White 160AX; 6 cylinder, 4 cycle, in-line gasoline
Transmission	230L Transmission Spicer 3461 constant mesh, 4 speeds forward, 1 reverse
Horsepower	Net: 147@3000rpm	Torque	Net: 325 ft-lb (440.7Nm)@1200rpm
Fuel capacity	60gal / 230L	Steering	Steering Wheel

	Mortars in Miniature ...A Scale Model Collection of the "Infantryman's Artillery"...