I found what I think is the best strategy in Buried if you want kills. What I mean by that is if you just hide in Juggernaut with trample-steams and head chompers, then what have you really accomplished. The game did everything for you.
My strategy is at Speed-Cola. You take the AN-94 and place it at Speed-Cola so you can have unlimited ammo. For me the Pack-a-Punched AN-94 is a great weapon till round 40 as long as you are aiming for the head and have the perma-perk Dead Shot Daiquiri. This strategy requires at least two people, but can have up to four. There are only two places that zombies will come from when you are at Speed-Cola. The top floor, there are two windows in the back where the box can spawn. If you stand next to Speed-Cola, all the zombies from those windows will come straight at you and you can line them up for easy kills. The other place is up the stairs. You want to take your best man and put him at the bottom of the stairs. Most of the zombies will come from this way and will line up for easy head shot slaughter. The reason I say put him at the bottom of the stairs is because if he gets overrun, then he has room to back up and time to ask for help.
Another reason this is an amazing place to make a stand is because there are two exits if things go wrong. Out the hole in the wall to where the box starts at and the hole in the wall that leads to the tunnel. Something interesting to note is that no zombies will come from these two areas. No zombies will jump up in the hole in the wall and no zombies will come from the tunnels unless you are inside of it.
Me personally, I put a trample steam on top of the roof of the building next to where the jail is so if you have to jump out the giant hole in the wall, you can run up the stairs onto the roof and use the trample steam to get back to Speed-Cola instead of having to run all the way around. Now just for back-up sakes, I put claymores and head chompers at the top of the stairs, so if the guy at the bottom gets overrun and goes down, all of that stuff will help you take back control.
My weapon choice is always the same. AN-94, Ray Gun Mark II and if I can the Paralyzer. All Pack-a-Punched. All 7 Perks. Claymores, Tramples Steams, Head Chompers, Galva Knuckles and Monkeys. Me personally, I hate the time bombs unless I'm playing solo, so everyone needs monkeys for when people go down.
Now at the beginning I said you can use up to four people in this strategy, but realistically you only need two. You can have two more up there with you, but if you want to make it easier on the guy at the bottom of the stairs then the other two need to do their own thing. I suggest train in front of Witch's House and in front of Jail. This way the zombies are split up into four groups and everyone is close by to help when people go down.
Now if you follow this strategy perfectly and have some people that know what their doing, then you my friend will be at the top of your leaderboards in no time. I hope that this guide has helped some of you that are new to this map or you that have always been hiding out in Juggernaut.
EDIT POST: This strategy dose NOT work solo. Just did this last night and made it to about round 35 and the zombies were coming in so quick that when they would try and jump down from the top and too many were jumping down so the ones that couldent decided to run around and come down the stairs. I had trample steams and head chompers and claymores, but they would still get in behind me. Now this would be an amazing two person strategy. One at the bottom of the stairs and one at speed colo to get the zombies at the top, but yet again DOSE NOT WORK SOLO!!!