Chemical Mortar Battalion - History

History

In 1935, the 2nd Chemical Mortar Battalion was established at Edgewood Arsenal Maryland with the chemical mortar as its primary weapon. At the onset of World War II, there were a few other mortar battalions and companies, including one that was lost on Bataan in the Philippines. In 1942, General George Marshall ordered the formation of five additional chemical mortar battalions equipped with the mortar. (These were the 3rd, and the 81st through 84th.) Later, the mortar was developed to be capable of instantly firing shells from a mere 565 yards (517 m) at minimum propellant charge, to a range of 4,400 yards (4,023 m) by having propellant-charge disks of powder added that by then were being manufactured as square disks with a hole in the middle, strung together, fitted into cartridges and sewn together into bundles of various thickness. Its rate of fire was 40 rounds in the first two minutes, 100 rounds in the first 20 minutes and thereafter a sustained rate of 80 rounds per hour. These variations were caused by the stresses and strains on the barrels and the rest of firing mechanisms that were being imposed by different firing conditions.

The mortars were transported in 3/4 ton trucks or on hand carts, in island engagements in the Pacific by boat, and in difficult terrain by mule.

During the Allied invasion of Sicily in the summer of 1943 - the first time the mortar had been used in war-time - 35,000 rounds were fired in 38 days, of which more than 90% were HE.