@Spurgeonryan
Once you complete the campaign, and play the Spartan Ops missions. Your still going to be out of your class as far as equipment is concerned. The reality is other players are going to have a decided edge over you, because they get bonuses that you won't be able to get for some time. That doesn't mean however that there isn't a work around. When you are ready to jump back online go with the SWAT play list.
That mode is a even playing field. Players don't get any bonuses, and everyone is forced to play with the same set of weapons. The lack of a radar decreases your map penalty, and the modes rules decrease the penalty you pay for your lack of experience. In the game mode the weapons are all precision, and head shots are one shot kills, and even body shots kill after three or four hits. So you won't have to deal too much with dancers. You know the guys you probably just met online. Who dance and jump all over the place to throw off your aim. You basically have more then enough ammo to take them down even if they do that crap.
Anyway play that game mode until you level up enough to actually have choices in what you are going to equip. The real upside however is I guarantee you will be getting kills in SWAT even if they are sloppy seconds. It is just really easy to steal kills from teammates in that mode, or at least avenge their deaths.