War Department Technical Manual: Ordnance Maintenance Gun and Top Carriage of 40-MM Antiaircraft Gun Materiel M2 (TM 9-1252; April 24, 1942)

War Department Technical Manual

Ordnance Maintenance Gun and Top Carriage of 40-MM Antiaircraft Gun Materiel M2

TM 9-1252

War Department, Washington, D.C., April 24, 1942

This manual is published for the information and guidance of ordnance maintenance personnel. It contains detailed instructions for inspection, disassembly, assembly, maintenance, and repair of the gun, recoil mechanism and top carriage of the 40-mm automatic gun Ml and 40-mm AA gun carriage M2, supplementary to those in the Field and Technical Manuals prepared for the using arm. Additional descriptive matter and illustrations are included to aid in providing a complete working knowledge of the materiel.

The 40-mm automatic gun M1 is intended for use against dive bombers and low flying aerial targets, filling an intermediate position between the high altitude guns of the 3 in. and 90-rnrn class and the cal. .50 machine gun.

It is designed to fire 1.96 lb. shells in rapid bursts at a rate of 120 rounds per minute, although it can be set for single-shot operation by moving the safe or fire lever on the left side of the breech casing to the position marked Single Fire.

The recoil system absorbs the shock of recoil and restores the gun to its firing position. The recoil action opens the breech, ejects the spent cartridge, and reloads and cocks the gun.

Cartridges are loaded in clips of four, and the empty cartridge cases are ejected from the breech with considerable velocity, which carries them through a system of troughing and throws them out in front of the gun.

Contents

• Introduction
• Inspection
• Trouble-Shooting
• Sight Assembly
• Barrel Assembly
• Gun Assembly
• Automatic Loader Assembly
• Recoil Cylinder
• Breech Ring Assembly
• Breech Casing Assembly
• Equilibrator Assembly
• Elevating Mechanism
• Traversing Mechanism
• Firing Mechanism
• Power Synchronizing Mechanism
• Platform Assembly
• Top Carriage Assembly
• Lubrication
• Storage and Shipping
• References
• Alphabetical Index

429 photos/illustrations