Jump to:
M3
M3A1

Scout Car M3^1-7,12

The scout car M2 had been based on the Corbitt 1.5-ton truck, was powered by Lycoming's "Corbitt Eight" MODGFC 94-horsepower V8 engine, weighed 7,900lb (3,600kg), and could travel at a maximum of 58mph (93kph). It had a cruising radius of 200 miles (320km), and a crew of 5-7 men. It was armored with .5" (1.3cm) plates on the front and .25" (.64cm) plates on the sides and rear. Four brackets for .30cal machine guns were mounted, two on each side. Twenty-two M2s, including prototypes, were produced from first quarter 1935-March 1938.

The 4x4 scout car M2A1, developed from the M2, was manufactured by the White Motor Company. It featured Tourelle skate mounts for its machine guns instead of the external pintle mounts found on the M2. The designation of M2A1 was changed to M3, and 100 M2A1/M3s were produced from 1937-9.

Top

                                                                                                                                                                                      

Scout Car M3A1^1-11

The M3A1 sported a wider body than the M3 with square corners and an overhung top, and its machine gun skate rail was lowered below the level of the armor. The rear door found on the M3 was deleted, and stowage and seating was changed. An anti-ditching roller was also added. A detachable canvas top was provided for the passenger compartment; it was supported by three bows and the windshield frame. The compression ratio in the JXD engine was raised to 5.88 from the M3's 5.78, yielding more power (110 gross horsepower at 3,000rpm and 241 gross foot-pounds of torque at 1,100rpm). The four-wheel drive system in these vehicles was full-time and could not be disengaged.

Beginning in mid-1940, 100 M3A1s were fitted with diesel engines for service testing with the Third Army. Two engines were used, either the Hercules DJXD or the Buda-Lanova Co.'s 6DT-317. The DJXD was a 6-cylinder, four-stroke engine that produced 103 brake horsepower at 2,600rpm and 233 foot-pounds of torque at 1,600rpm; the 6DT-317 was a 6-cylinder four-cycle solid-injection type that made 81 horsepower at 2,300rpm and 220 foot-pounds of torque at 1,200-1,600rpm. Starting the diesel engines required more torque and speed, so a second 12-volt battery was installed under the left-side door in a compartment similar to that for the original battery. The batteries were connected by a series-parallel switch so that when the starter button was pressed, they acted in series to power the 24-volt starter, and when the starter button was released they powered the normal 12-volt electrical system in parallel. When the testing was completed, the diesel cars were fed back into production so that usable parts could be recycled.

Top

                                                                                                                                                                                                                                       

References

1. Hunnicutt, R.P. Armored Car: A History of American Wheeled Combat Vehicles. Novato, CA: Presidio Press, 2002. Reprinted from Armored Car, R.P. Hunnicutt ©2002, available from Presidio Press, 505B San Martin Drive, Suite 160, Novato, CA 94945.
2. TM 9-705 Scout Cars, M3, M3A1, and 4.2 Mortar Motor Carriage, M2. Washington, DC: War Department, 19 February 1941.
3. Doyle, David. U.S. Half-tracks: The Development and Deployment of the U.S. Army's Half-track Vehicles, Part one. Ed. Pat Stansell. Delray Beach, FL: The Ampersand Publishing Group, Inc., 2014.
4. AGF Board No. 2. Development of Armored Vehicles, volume II: Armored Cars, Scout Cars, and Personnel Carriers.
5. Crismon, Fred W. U.S. Military Wheeled Vehicles. Minneapolis: Victory Publishing, Ltd., 2001.
6. Tank Data, vol. 3. Aberdeen Proving Ground, MD: US Army Ordnance School, Jul 1958.
7. TM 9-705 Scout Car M3A1. Washington, DC: War Department, 26 October 1942.
8. Catalogue of Standard Ordnance Items, 2nd edition 1944, volume 1. Washington, DC: Office of the Chief of Ordnance Technical Division, 1 June 1945.
9. Sola, Samuel, Vincent Bobkowski, and Kara Crocker. Weapon Mounts for Secondary Armament. Santa Monica, CA: G. O. Noville & Associates, Inc., April 1957.
10. TM 9-2800 Standard Military Motor Vehicles. Washington, DC: War Dept., 1 Sep 1943.
11. Hogg, Ian V. The Greenhill Armoured Fighting Vehicles Data Book. London: Greenhill Books, 2000.
12. FM 30-40 Military Intelligence Identification of United States Armored Vehicles. Washington, DC: War Department, 21 May 1941.

Last updated 13 May 2023.
Questions? Comments? Corrections? Email me
© Copyright 2012-24 Chris Conners