The estate of the late John Sayen has graciously given the Tactical Notebook permission to serialize his study of the organizational evolution of American infantry battalions. The author’s preface, as well as previously posted parts of this book may be found via the following links:
In March of 1940, the Army adopted tables of organization that set the strength of an infantry regiment at 2,776 officers and men. Six months later, after the fall of France (June 1940) and the signing of the Selective Service Act (September 1940), a new set of establishments, dated 1 October 1940, increased that number to 3,449.
The reorganization of March 1940 imposed two substantial changes upon rifle companies. The first of these was the addition of an eight-man automatic rifle squad to each platoon. The second was the splitting of the company headquarters into two organizations: the company headquarters and the weapons platoon.
The weapons platoon broke down into three elements: a headquarters, a mortar section, and a light machine gun section. The headquarters consisted of a platoon leaders, a platoon sergeant, two messengers, and a driver for the half-ton truck. In addition to the personal weapons of these soldiers, it was armed with a pair of Browning Automatic Rifles (BARs.)
With two five-man mortar squads, the mortar section of March 1940 bore a close resemblance to that of December 1938. Indeed, the only major change was the transfer of the mortar section’s half-ton weapons carrier to the platoon headquarters. (Notwithstanding the loss of its truck, the mortar section continued to rate a third 60mm mortar.)
The two squads of the light machine gun (LMG) section lost two men apiece. Each thus consisted of five men and a single M1919A4 machine gun. (The section also possessed two spare machine guns. When not in use, these would normally be carried, along with the spare mortar of the mortar section and the spare BARs of the automatic rifle squad, in the half-ton truck of the platoon headquarters.
The addition of an automatic rifle squad to each rifle platoon restored some of the BARs that had been taken away by the tables of organization of December 1938. (Each automatic rifle squad possessed three BARs. Two of these were carried by the squad at all time. The third was a spare.)
The authors of the establishments of March 1940 imagined that the automatic rifle squad would provide the platoon commander with a means of covering an otherwise open flank and, when the platoon was in the defense, delivering enfilade fire across the front of the platoon position. It could also be used as the “firepower reserve” of the platoon, to deliver a high volume of fire at a moment of crisis or opportunity.
The platoon commander also enjoyed the option of dividing the automatic rifle squad into two or three teams, each of which could be used to reinforce a rifle squad or employed as a stand-alone element. However, in the view of the officers who wrote articles explaining the thinking behind the new organization, the splitting of the automatic rifle squad was reserved for unusual situations.
The tables of organization adopted in October of 1940 eliminated all of the spare weapons called for in the establishments approved in March of that year. In the case of the mortar sections of weapons platoons, this was done by providing the spare weapons with crews. In the case of the spare machine guns of machine gun sections, the spare weapons were taken away.
At the same time, the headquarters of each weapons platoon received a second half-ton weapons carrier. Thus had the effect of both reducing the load carried by each vehicle and increasing the ability of the weapons platoon to carry ammunition. (Each of the weapons carriers was provided with a mounting that allowed the use of the two BARs of the weapons platoon as anti-aircraft weapons.)
In addition to the men of the third squad of the mortar section and a driver for the second weapons carrier, each rifle company received twenty-one “basic” privates. These men, who had received neither specialized training nor permanent assignments, filled gaps in squads created by leave, sickness, guard duty, working parties, and kitchen police. (Six of the basic privates were allocated to the weapons platoon, five to each of the rifle platoons.)
Editor’s Note: The format of the many appendices to this work fit poorly with Substack. For that reason, I have placed them on a PDF file that can be found at Military Learning Library, a website that I maintain.
Sources:
US Army Adjutant General Table of Organization 7-11 “Infantry Regiment, Rifle” (Washington DC 6 December 1938, 1 March 1940, and 1 October 1940)
US Army Adjutant General Table of Organization 7-17 “Infantry Company, Rifle” (Washington DC 1 October 1940)
George A. Lynch “Some Reflections on Infantry Material and Tactics” Infantry Journal (March-April 1939) pages 294-295
“Firepower, Manpower, Maneuver” Infantry Journal (November 1939) pages 498-505 and 606
“Tactics of Rifle Company Elements” Infantry Journal (May-June 1940) pages 292-298
“Tactics of the Auto Rifle Squad” The Infantry School Mailing List (February 1941) pages 1-13
“Supply” The Infantry School Mailing List (July 1941) pages 257-260