Because of the many troubles encountered in this work the various stove makers in the summer of 1918 formed an association which they called the Six-inch Trench-mortar Shell Manufacturers' Association. This association held monthly meetings and its members visited the various plants where shell castings were being made. The United States Radiator Corporation, the Foster-Merriam Co., and the Michigan Stove Co., were especially active in improving methods for making these shell.
The various concerns producing 6-inch mortar shell and the amounts turned out were as follows:
Foster Merriam Co., Meriden, Conn. 33,959 U. S. Radiator Corporation, Detroit, Mich. 240,700 Globe Stove & Range Co., Kokomo, Ind. 17,460 Rathbone, Sard & Co., Albany, N. Y. 97,114 Michigan Stove Co., Detroit, Mich. 100,000
The following concerns shortly before the armistice was signed received contracts for the production of 6-inch mortar shell, orders ranging in quantity from 50,000 to 150,000, but none of these concerns started production:
Wm. Crane Co., Jersey City, N. J. Frontier Iron Works, Buffalo, N. Y. Henry E. Pridmore, (Inc.), Chicago, Ill. Best Foundry Co., Bedford, Ohio. McCord & Co., Chicago, Ill.
It was not until July, 1918, that the plans were ready for the 4-inch Newton-Stokes trench mortars. The American Expeditionary Forces estimated that they would require 480 of these weapons. A total of 500 drawn barrel tubes was ordered from the Ohio Seamless Tube Co., of Shelby, Ohio. This concern was able to ship one-fifth of its order within 10 days after receiving it. The barrels were sent to the Rock Island Arsenal for machining. The Crane Co., of Chicago, held the contract for building the bases, tripods, spare parts, and tools, and also for the assembling of the completed mortars. This factory was already equipped with tools for this work, since it had been building similar parts for 3-inch mortars. Consequently, the Crane Co., in August, almost within a month of receiving its contract, was producing completed 4-inch mortars and sending them to the Rock Island Arsenal for proof firing. The Ohio Seamless Tube Co. reached a high daily production of 83 barrel forgings per day; the Rock Island Arsenal, 10 machined barrels per day; and the Crane Co., 19 assembled mortars per day.
