How to get a nuke with m16a4 in MW2 PS3?

heartbeat sensor is a no no because it only gives away from a distance and like the guy above me said will distract you from the actual screen you will be staring at the little radar until it picks up something and chances are that people use ninja pro which makes you invisible to the heartbeat sensor go with the silencer it you will be able this way it will be harder for you to get spotted when you kill someone other than that the whole class is great I used almost the same class but instead I used an LMG