Left 4 Dead 2

This particular achievement can be won in any Campaign.
The only stipulation is that you need a clear enough path to run far enough.

You must just simply grab a survivor and allow the Charger to carry him/her off.
The charger stops after 80 feet has been accomplished in a charge. You must not hit anything that will stop the charge (i.e. a bench, wall, tree, etc). This may take some time to get. But, once you stop charging in an open spot after a charge and start bashing the survivor, the achievement is yours.

The Park in the Parish Campaign and the Atrium in the Dead Center Campaign are great places to try for this achievement.

Personally I prefer a good video than an explanation concerning some achievements. I found this video on Youtube and it worked at perfection. Plug in 2 controllers, start a versus match with your main account as infected and the second controller as survivors. Then start Dead Center, chapter 1, go through the level until you reach the windows shown in the video (reach the windows will take you less than a minute) and place your guest just in front of the vacuum. With your first controller kill yourself until you have a charger and finally do exactly like the video and you will unlock your achievement :)

Thanks you to [FDRDLOP] Clan for the video , it's not mine I just found it on youtube.

I got this by playing on Versus mode in the Dead Center campaign. Start the campaign on the second chapter (The Streets). The person who wants the achievement should be the Infected and have either a second controller or some friends play as the Survivors. If you have any bots on the Survivor side, just incap them in the safe room. If the person going for the achievement doesn't spawn as the Charger, just have the survivors kill you until you spawn as the Charger. Once you are the Charger, go the right most post (facing the CEDA tent and the fence) and have one of the Survivors stand in front of you. Make sure the Charger is lined up so that you can carry the Survivor past the fence and close to the CEDA tent. Once everything is set up, just hit RT and keep going. If you hit the potted plant to the left of the fence you will still get the achievement (that's what I did and I still got it). This can be done to also get the Meat Tenderizer achievement.

This achievement is much easier than it sounds. When I first read it, I thought, "80 feet!?" but remember, the Charger is FAST and covers that kind of ground in a second or two.

With that said, all you need to do is line up a survivor so that your charge path won't lead you into a tree or a wall, or car or anything... Hard Rain has many open areas like streets, corn fields, open swamps... Charge a survivor and assuming you don't miss or hit anything, the achievement will pop. Good luck!

theres a good spot in the dark carnival campaign in chapter 4 (i think) the barns - once you come out the barn instead of going up the ladders, to the right is a loooong path back down the side of the barn - just get a charger and get a friend/second controller to stand at one side and ram them down the path and Ding!! achievement unlocked :)

you can easily get this acheivement by charging someone well over 80 feet. here is how.
you can do this split-screen on no mercy. just load up the last map and have the person going for the acheivement be the infected and just let the other kill you until you are a charger. then wait, soon the survivors will have just gotten to the roof and then there will be a helipad followed by a ramp. the survivor should stand on the helipad just in front of the ramp (you can also make it a little easier and kill off the survivors other than the human player) and wait for the other person to charge them off of the building, wich is well over 80 feet. and then bleep-bloop, this acheivement is yours