Forum:Best weapons for COD:MW:R multiplayer

Ive got call of duty: modern warfare: reflex and i can never find the best weapon for me. im only a corpral II, and right now my custom class is: M249 SAW with red dot sight, USP.45, perks are: special grenade x5, uav jammer and extra bullet damage. can anyone suggest what the best guns to use are and what rank i need to be to get it.