What sniper rifles were used by US Marines in the Vietnam War?

Answer 1) The sniper version of the M14 (an evolution of the M1 Garand used in WW2) was used by the USMC until 1964 or 1967 (depending on which source you consult), after which they used the specially made Remington M40. Answer 2) During Vietnam the sniper that the USMC primarily used was the Remington700. They needed this because during World War I and World War II standard infantry weapons with scopes on them were used. The M14 was also replaced with the M16 during the Vietnam War, but was nonetheless used during the war.