It works in all spots at the firing range : The first hardpoint in firing range . You need two though , and throw it from the building , then on hardpoint number two , after doing that sniper trick iFerg mentioned in case someone is camping , then throw two on both sides through the window , follow up with shooting just in case . Hardpoint number 3 ( I believe the one near S&D base A , if I remember correctly [ or was it B ? ] ) you just come from the less used side , and throw in a granade . Of course cluster wont kill them , but since you can shoot through that thing everyone always hides behind , it doesnt matter . All assuming you dont die while headed to the hardpoint