First things first ur class will need coldblooded. Next u will need to play in games till the outher team gets a strike copter or plavlow. The best game modes for his will be domination, groung war, or headquarters. Now you will just play till the outher team calls there helicopter in and wait till one of ur team mates shoots it down and here is where it will start spinning or blow up. If it is spinning you are going to shoot it with your class that has the coldblooded perk on it. the best gun to use would be a (LMG) but i would use an assult rifle but its ur choise. Now once your start shooting it, each bullet that hits the helicopter will count as a kill so once u shoot it with a whole clip from your (LMG) you should have ColdBlooded pro and u most likely have ranked up cause u get alot of points with it so good luck and please post if u like this tut i have made. Ill be getting a youtube vid for proof and to help you guys out....