The two primary pieces used by American artillery battalions in World War II were the 105mm howitzer (M2A1) and 155mm howitzer (M114) . The triangular structure of the World War II infantry division called for three battalions of 105mm supporting each of the three infantry regiments of the division and one heavy battalion of 155mm howitzers, which was used at the discretion of the Division artillery commander. The 105mm M2A1, along with its many variants, was the most widely used light artillery piece in the American inventory. Between 1941 and 1945, 8,536 were produced.
The 155mm howitzer was used as both divisional and non-divisional artillery. In the 106th, it was used by the 592nd and also by the non-divisional 333rd. It fired a 95 pound shell, and had a range of 9 miles. A crew of 11 was required. It was normally towed by an M5 HST tractor.
Other artillery pieces that were used extensively throughout the war were the 8 inch and 240mm howitzers as well as the 75mm pack howitzer (Marine and Airborne units early in the war). The former two were strictly used within the non-divisional framework. A 4.5 inch gun was also part of the American arsenal but in relatively small numbers.