M3A1 Half-track 9th Armored 27th Infantry, B Company

The U.S. produced more than 40,000 half-tracks from 1933 and 1944 – of the dozens of half-track variations produced, the M3 and M3A1 Half-track Personnel Carriers were among the most widely used. As the name suggests, these vehicles were used to move men across beaches, through mud and snow and forests on every front, and also served as a prime mover for the M5 3-inch anti-tank gun. Initial M3 production contracts were awarded to both Autocar and Diamond T in September and October 1940, respectively. Meetings between Ordnance, Autocar, White Motor Company, and Diamond T during those months led to the formation of the Half-Track Engineering Committee. Comprised of representatives from these organizations, the Committee’s objective was to create half-track vehicles with as many common components as possible. Near the end of production, the M25 pedestal mount with .30 caliber M1919A4 was replaced with a M49 ring mount and M2HB .50-caliber machine gun over the co-driver’s seat. With the change in gun mounting the model designation was changed to M3A1. Pleased with performance and reliability of the vehicles, the basic half-track design was soon adapted for a variety of uses beyond the original prime mover, personnel, and mortar carrier roles. Many of these adaptations were expedient variants. As the war progressed the intention was to replace not only the expedient variants but the halftracks themselves with fully tracked, more heavily armored vehicles.