Don't forget to duck, protect those toes, nothing worse then dying from getting shot in the feet. I always ran stun grenades, slows them down makes it easier to get that second bash in! Secondly, run Semtex not frags! Also perks similar to lightweight/marathon/blast shield work wonders as well. In MW2, C4 also worked excellent with riot shield. Basically, I've found the run, crouch, stun, bash, repeat process a good one.