I take that you were playing bridge... Well, if you were on assault then it would be a bit harder but I do this all the time on defense and kill up to 5 guys. First, you go up the ladder then hide behind the wall for a few seconds. Get in crouch position and check if anybody is guarding the other side. If they are, then shoot him (You will have advantage since you are down low) Now when you are half way go into prone. Make sure to check if anybody is on the left corridor. Go into crouched position, making sure no sniper or grenadier is on the tower. Throw a grenade (Still hiding behind the wall) at or near each car/truck. They usually hide behind the cars... Now most or all of the guys should be dead. If not, then just throw another grenade in if you know he's there or search for campers/afk's. If you meant assault then you should wait until everything is clear or throw a grenade (They tend to hide behind the walls) The reason you should wait is because they have snipers and grenadiers waiting to take you out.

I hope this helps.

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