This report covers tests which were conducted to determine if the additional weight of a weather protection shield for the 3-in.50 Caliber Single Mounts, Mark 34 and Mods., would adversely affect the train power drives. The shield will be constructed of metal, and will prevent icing of the exposed mechanical linkages of the 3-in.50 Caliber Rapid-Fire Loaders Mark 2 and Mods. The shield and fire control components are estimated to weigh between 1500 and 2000 pounds. A standard production 3-in.50 Caliber Single Mount was used for the tests. Blocks of steel were placed about the mount platform to simulate the weight of the weather shield, fire control components, and other miscellaneous gear. A series of firing tests and temperature rise tests were conducted to determine whether the train power drive would be adversely affected by the increase in weight and inertia.