Knife is hard, no question about it. I recommend a full (64 player) Karkhand server for both badges. I got all three of these (basic & veteran pistol, basic knife) on full karkhand servers as USMC.

First the pistol. Spawn at the left forward spawn point and move parallel to the road leading in to the city. Right at the city entrance on the left side of the road is a wrecked APC that's built in to the map (it is not a player APC that has been blown up). You can crawl underneath this thing from the rear and you're pretty well hidden and in a shadow. You get people both in the city and as they come out the hole in the corrugated metal fence to your left. MEC spec ops like to come out that hole and take a left and move to where you're hiding. They put C4 on the road and blow up tanks entering the city. Keep looking left and pick these guys off. Use the UAV and don't be surprised by them. Keep checking the left. When you shoot the pistol, use the sights (takes a few minutes to figure them out, but your bullet will hit at the top center of the forward sight just like in a real pistol). You will need to shoot an opponent quite a few times to kill them with the pistol. Use the recoil to help you -- first shot at the belt, then rapid fire as quickly as possible without moving the mouse. You will strike them progressively higher with each shot because of the recoil. You've got to shoot them repeatedly and quickly. Another trick is to play as sniper. Shoot them once with the rifle, then switch to the pistol and one shot will finish them off. This is harder for me because you've got to aim again after switching weapons.

Knife. Spawn as USMC at the same place as pistol. Move forward to the corrugated metal fence. From the hill, use the rifle to shoot anyone on that street. When the street is clear, go through the fence opening and sprint across the street and into the little notch on the wall to your right. Hide there for a second. When the coast is clear, continue up the road to the alleyway that leads to the right. From this alley you can see the Hotel spawn flag. That alley is a spawn location for Hotel spawners. You can stab 2 or 3 of them sometimes before they get you. The knife is a 1-hit kill, so stab them and immediately get another target. You know if you hit them by the sound that the knife makes when it hits. This is a good place to get pistol kills, too. If nobody is there, hide behind the dumpster so you aren't picked off by Hotel flag defenders. Just wait a few seconds and a new batch will spawn. Usually there will be a sniper laying in that alley and you can just walk up to him and knife him.

You can also approach this alley by staying in the field to the right of the fence and going through the opening at the end by the brick wall. I prefer the street because you have better visability.

The ranking and badges are really fun. I have 39 knife kills. After I get 50, I want to try to get the veteran knife badge. It has the same requirement as basic: 7 kills in a round, but you've got to have 50 globally first.

Let me know how it works for you!

Jim