DayZ has a variety of different weapons. There are many different factors to consider when choosing which weapon to use. The main thing I worry about is how loud the weapon is, in other words what range can the weapon be heard. There are 2 types of audio ranges one for players and one for zombies, sometimes they overlap, sometimes they don’t.
The next thing I think of is how easy it is to find ammo for the weapon. This chart does show the ammo type, but does not show the scarcity or rarity of the ammo. For example, it is not too hard to find an AK-74 or it’s variants (Kobra, AK-74U). These are pretty nice guns because although the damage is not high, they are kind of quiet in comparison to the AKM or M-16. The problem is that the AK ammo (the orange magazines that come in green pouches) can be very hard to find sometimes. AKM ammo (looks like a black AK mag on the ground) is very common.
Use this chart to compare the various audible ranges, ammo types, damage amount, and fire modes. Unfortunately it does not show the weapons firing range. obviously the sniper rifles have a very long range while the shotguns have a very low range. I read somewhere that the revolver has a higher range than the M1911 so keep that kind of thing in mind as well.
Old, outdated chart below in case Rocket changes it back.