A photograph taken in the mid-1960s shows a U. S. soldier in Vietnam holding a World War II German MP 40 submachine gun. At first glance, the image seems puzzling, but the explanation lies in one of the most secretive military units of the entire conflict.
The soldier was a member of MACV-SOG, short for Military Assistance Command Vietnam Studies and Observation Group. Despite its harmless-sounding name, the unit was one of the most lethal American forces deployed to Indochina, and it operated under the direct influence of the CIA rather than the regular U. S. Army.
MACV-SOG consisted largely of Green Berets who conducted deep reconnaissance missions far behind enemy lines. They infiltrated North Vietnam, Laos, and Cambodia to destroy truck convoys, ammunition dumps, supply bases, and other key logistics targets. Their main focus was disrupting the Ho Chi Minh Trail, the vital supply route used by North Vietnam to arm communist guerrillas in the South. The problem was that the United States could not publicly admit to having troops inside so-called neutral nations like Laos and Cambodia.
To preserve deniability, MACV-SOG teams wore unmarked uniforms, carried no identification or dog tags, and were armed with foreign weapons that could not be traced back to the U. S. military. The weapon most associated with early MACV-SOG missions was the Swedish Carl Gustaf Model 1945 submachine gun, known as the Swedish K.
Supplied by the CIA with 9mm ammunition, it had a folding stock and a 36-round magazine. Operators carried heavy loads of ammunition, often one magazine in the weapon and at least a dozen more in pouches, giving them roughly 468 rounds. A unique feature of MACV-SOG teams was that operators had the right to choose their personal weapons. A typical team consisted of two or three American Green Berets and four to six South Vietnamese soldiers.
The Americans could pick from any foreign weapon that suited their mission, as long as it was not U. S. -made and therefore untraceable. This is how some MACV-SOG soldiers came to carry the German MP 40.
The weapon was already present in Vietnam from two sources: captured World War II guns that the Soviets had stored and later distributed to communist allies such as the Viet Cong, and leftovers from the French colonial era. French forces had used captured German weapons during their long, unsuccessful campaign to hold onto Indochina before withdrawing in the late 1950s. MACV-SOG personnel who requested the MP 40 obtained it through the same secret CIA supply channel used for other gear. The CIA reportedly had access to nearly any weapon anyone could want, along with spare parts and ammunition.
The MP 40 was a practical choice for the close and mid-range engagements typical of jungle warfare. It was known for being highly controllable in automatic fire, thanks to its design, low rate of fire, and 9mm ammunition. It was also relatively lightweight at about 8. 85 pounds and offered a sturdy, stable platform.
Comparisons with standard weapons of the era highlight why some operators preferred it. The MP 40 kept its sights on target far more easily than the standard American M-16 of the Vietnam War. Some MACV-SOG units, naturally, used enemy weapons from the Soviet AK family, since firing the same type of weapon as the enemy made it harder for sounds to give a position away. But even the AK bounced around in fully automatic fire, while the MP 40 remained noticeably more controllable.
The MP 40’s magazine held 32 rounds of 9x19mm Parabellum ammunition, comparable to the Swedish K, though the German weapon was more expensive to produce. Several photographs from the period show MACV-SOG operatives wearing distinctive World War II U. S. Marine Corps M42 duck hunter camouflage uniforms while carrying MP 40s.
Later in the war, once substantial numbers of U. S. weapons had been captured and used by North Vietnamese forces, the requirement for deniability regarding U. S.
equipment was dropped. A new American weapon was then designed specifically for MACV-SOG: the XM177. The XM177, a CAR-15 version of the M-16 and the predecessor of today’s M4 carbine, had a 10-inch barrel on its earliest versions and a distinctive 4. 2-inch compensator flash suppressor.
It was officially issued with 20-round magazines, which were considered inadequate for MACV-SOG missions. Some team leaders purchased 30-round magazines through Guns & Ammo magazine and issued each man one 30-round magazine alongside the government-issued 20-rounders. Interestingly, some MACV-SOG recon men still preferred the suppressed World War II M3A1 grease gun in . 45 caliber.
That weapon had been developed by the OSS, the CIA’s predecessor organization, and, like the MP 40, offered a very controllable rate of fire of around 450 rounds per minute. It is generally believed that by the late 1960s, World War II weapons such as the MP 40 were phased out of MACV-SOG service and replaced by the XM177.