If you haven't used the shield for plant cover or written it off, try it with a sniper rifle like you'd normally sharpshoot with or with an LMG.
Snipers that like to overlook large areas that leave you open, such as the top floor beside C on Standoff or the opposite window, planting a riot shield before you prevents body shots as well as grenade kills if the blast isn't between you and the shield. Flak Jacket and Tactical mask helps for sure.
It sounds horrible on paper but in practice, made for excellent control over B due to the little eye-hole, allowing you to bead enemies and sit up with a headshot/bodyshot while the enemies are forced to only headshot you.
Using it on Express before B with an LMG with FMJ yielded great results.
I recommend it only with LMGs or Snipers due to how quickly you're going to be blowing through ammo doing this. Running Scavenger helps but you'll going to be pounded on since so many people want to flood right back to you so you'll have little time to grab a pack.
These methods work great but be wary of your flank and don't wear out your welcome. They WILL use heavy explosives and launchers and your shield can only take so much. Hopefully by the time this happens, you've reached your scorestreaks or your team at least has B well under control.
Try to plant as close to side cover as possible when you do, so at least you are only open on one side.
Cool I'm going to give this a go tonight. I haven't managed to use lmgs effectively yet due to awful ads times and if you sit and try to pick a few off you just get shot in the back/naded.
LSAT, I got it to max way too fast. That thing is a beast, for any LMG the target finder sight is a must. Almost feels like the chopper gunner from BO, plus you need a grip and probably the toughness perk to help even the odds against SMG users. But then again, some people are fools and they fall for the old dance in a circle with an assault shield trick.
I love using the shield against snipers, they think they can shoot through the shield and I just wait till they reload before I smash their face in. Two taps a do ya!
Everyone on GameFaqs pretty much is a troll. This site honestly has the WORST user base I have ever seen. -Tuggboat1121