Okay, I have found a few ways to boost - just thought I'd post it for those that didn't know.
First Way:
Two WE>u people join an SnD, on opposite teams. You both need either One Man Army, or Riot Shield/Spas-12.
Firstly, find somewhere safe for you and the other to meet up. One holds out Shield, other one hammers it with bullets/shells (via shotgun). After so many shots you get +500 points (EXP).
Once the points start to die down, tell them to stop and swap to your Spas, or swap classes. Then the other person pulls out their shield and rinse/repeat.
Classes:
Riot Shield w/ Spas-12
- One Man Army
- Whatever
- Whatever
Use RPD/whatever on another class when using One Man Army.
Second Way:
Requires lots of people in Domination - a full game.
One team caps C, the other caps B, and you leave A uncapped.
Then just keep swapping caps on B.
Obviously when doing this you DO NOT KILL ANYONE.
Enjoy,
Ferocity.