The M79, also known as the "Thumper" or "Bloop Tube" for its distinctive firing sound, is an American 40mm shoulder-fired grenade launcher designed by the Springfield Armory in 1960. It was widely used during the Vietnam conflict, although quickly replaced by the M203 in later years. During the its time in service, there was an average of one M79 for every ten man squad.
In Battlefield Vietnam, the M79 is issued to the AmericanHeavy Assault kit. It has a single round per reload and has 5 grenades in reserve. It is mainly a weapon for anti-infantry purposes, but it can also be used to some effect against light vehicles and even tanks.
The M79 has a large blast radius and very high damage, making it very effective against infantry. In close quarters, although it's potentially harmful to the user, aiming it is barely even required to have a kill on an enemy. At long ranges, the M79's grenade has a huge arc in its trajectory, making it difficult to use, but this can also help in using it like a mortar, sometimes even shooting blankly at a choke point can result in a few kills.
Against vehicles, the M79 can easily kill everyone inside a jeep. It can't destroy a tank on its own, but, with enough damage from anti-tank weapons being inflicted, the M79 can aid in destroying a tank. It's relatively ineffective against helicopters, because the slow velocity of the grenade and the arcing path can make it near impossible to hit a helicopter.
Because Battlefield Vietnam features different loadouts for each faction, this list may not be specific enough. Please see each faction's respective page for information on individual weapon kits and loadouts.
"A 40mm grenade launcher, called "Thumper" or "Bloop tube" by soldiers due to its distinct firing sound. It increases the firepower of infantrymen by allowing them to fire accurate, high explosive projectiles."
— In-game description
In Battlefield: Bad Company 2: Vietnam, the M79 is issued as a gadget to the Assault kit. It is the equivalent of the 40mm Grenade from the base game. Like the version in Battlefield Vietnam, it has a yellow striped camouflage. This special yellow/orange tiger stripe camouflage is a reference to The Roach's M79 from the Francis Ford Coppola film "Apocalypse Now", set in the jungles of Vietnam in 1967. The Roach appears to be high on drugs when he is called to use his M79.
The M79, compared to the 40mm Grenade Launchers from the base game, is more difficult to use effectively due to the ineffective iron-sights. On the positive side, the M79 is quieter than the 40mm Grenade Launchers, and has a faster reload time as well.