In August 1966, North Vietnam’s Central Office for South Vietnam (COSVN) reorganized its forces in the Central Highlands, disbanding two under-strength divisions there that had been heavily mauled that summer and spreading their personnel and equipment among other surviving units. Five of the regiments and four newly arrived infantry battalions were consolidated into three regiments, the 24th, 33rd and 95B, and given the task of conducting guerrilla operations in conjunction with Viet Cong units. They were also directed to support the newly formed mobile strike unit centered on the 1st NVA Division. Its three infantry regiments (66th, 88th and 320th) were reinforced by one of the battalions from the disbanded division’s 101st Regiment. Also, four artillery battalions drawn from those divisions were added to the NVA’s 40th Artillery Regiment assigned to support the mobile strike force. Soldiers from the U.S. 173rd Airborne Brigade and 4th Infantry Division would become intimately familiar with those regiments and their supporting mortar and rocket units in the battles around Dak To in 1967. Of the NVA’s supporting arms in those battles, the DKB 122mm rocket was the most commonly employed, but the M-43 120mm was the most powerful. Used sparingly and usually against a fire support base or special forces camps, the M-43 delivered a lethal punch, equal to that of the much larger 152mm howitzer use near the DMZ and the Cambodian border.
A battalion support weapon in Soviet practice, the M-1943, or M-43, mortar was a production and operational improvement over the prewar M-1938. It retained the M-38’s circular base plate and two-wheeled carriage but has longer shock absorber cylinders. Compared to recoilless rifles, RPGs and smaller mortars, however, its weight limited its employment in the war’s early years to set–piece battles of the NVA’s choosing. After 1972, as the NVA increasingly utilized motor transport, it saw much greater use.
The M-43 can be towed or broken down into barrel, base plate and bipod. It served as a regimental and division support weapon in NVA service. The mortars were typically allocated to artillery regiments and then farmed out to infantry regiments conducting offensive operations against fixed positions. A simple, robust and easy-to-maintain weapon that requires little training to operate, the deadly and effective M-43 remains in frontline service with the People’s Army of Vietnam to this day.