Call of Duty: Modern Warfare 3 Tips

Easy Juggernaut kills(spec ops. survival mode)
To easily kill juggernauts, use flash bangs on them. they will be stunned for a few seconds,giving you enough time to shoot him without getting shot back. or, try using predator missiles,explosive weapons(RPGs,M203s,etc.),sniper rifles or LMGs. (but ALWAYS flashbang him.) the GIGN riot team is also very effective against him. deploy the riot team, find a nice corner to camp,and once the "jug" enters, the riot shield squad will unload on him and he will be unable to kill them due to their riot shields. But if you haven't unlocked the said items above,then you'll have to rely on flashbanging the big guy then headshot.
Hope this Helped, see you online.