Use the Grim Reaper to destroy the MG emplacement.
During the mission "Victor Charlie", you will detonate the explosives with . Once you get around the corner, you will pick up the Grim Reaper to destroy the ZPU on the river. After this, you will be told to go left and to kill a couple enemies in the buildings. While you approach the marker and objective to "Clear out North Village", you will enter a building. Approach the right window with the Grim Reaper equipped and aim out the window. In the middle of the hill at the top you will see a big pile of barrels and trash. Once you reach the edge of the window, all the trash will blow off and a MG will appear. Use the Grim Reaper to shoot and destroy the MG placement with one shot.
When you have to take out the ZPU, A marine carrying the "Grim Reaper" will be killed, you hear someone calling for Mason to pick up the 202. It will glow bright yellow. Just for anyone who cant find the launcher
Wait, nevermind....to answer my own question: Once you destroy the ZPU and toss a grenade into the "Spider Hole" Woods will tell you to lead the way through a hut, once in the hut, continue forward and an MG will appear. Whip out the Grim Reaper, and blow the MG to bits!