If you're pretty careful about only engaging one zed at a time and have good aim, you can take them down with a single shot to the head. I find this really important in the first hour or two when ammo is scarce and you're still scavenging for the basic essentials.
I've been getting into this for the past week now. Not sure where you're playing at on the map, but I've been able to load up on ammo pretty quickly after spawning it. Found its just easier to run through a small town, allowing the Zeds to chase me. Find a barn or house, park myself away from the walls and take them out with head shots as they try to come through the door. Loot the place and move on. Seems easier than sneaking.
If you're using a long rifle to kill hordes in the buildings, then switch to handgun as the hordes diminish. Lower noise keeps the whole viallge of new spawns from filling your building.
Will be fun now to try with a group of my friends Friday, though I'm sad to lose a life that I have marched all the way to Stary Sobor just so they can join up close to me on the beach