Rarity in WarZ

Question:

On Another Q and A thread, @chickenputty posted this:

//RIFLES
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + "FAMAS (I)", Material.WOOD_HOE, 1),
ChestType.Gun).setRarity(45).setMinZone(0).setMaxZone(4));
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + "M16A4 (II)", Material.STONE_HOE, 1),
ChestType.Gun).setRarity(40).setMinZone(3).setMaxZone(5));
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + "M4A1 (III)", Material.IRON_HOE, 1),
ChestType.Gun).setRarity(20).setMinZone(4).setMaxZone(100));
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + "AK-47 (IV)", Material.DIAMOND_HOE, 1),
ChestType.Gun).setRarity(10).setMinZone(5).setMaxZone(100));
//SMGS
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + "MP5 (I)", Material.GOLD_HOE, 1),
ChestType.Gun).setRarity(45).setMinZone(0).setMaxZone(4));
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + "Uzi (II)", Material.RECORD_11, 1),
ChestType.Gun).setRarity(40).setMinZone(3).setMaxZone(5));
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + "UMP45 (III)", Material.GOLD_PICKAXE, 1),
ChestType.Gun).setRarity(20).setMinZone(4).setMaxZone(100));
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + "P90 (IV)", Material.GOLD_SPADE, 1),
ChestType.Gun).setRarity(10).setMinZone(5).setMaxZone(100));
//SHOTGUNS
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + "M590 (I)", Material.WOOD_PICKAXE, 1),
ChestType.Gun).setRarity(45).setMinZone(0).setMaxZone(3));
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + "AA12 (II)", Material.STONE_PICKAXE, 1),
ChestType.Gun).setRarity(40).setMinZone(3).setMaxZone(4));
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + "M1014 (III)", Material.IRON_PICKAXE, 1),
ChestType.Gun).setRarity(20).setMinZone(4).setMaxZone(6));
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + "SPAS-12 (IV)", Material.DIAMOND_PICKAXE, 1),
ChestType.Gun).setRarity(10).setMinZone(5).setMaxZone(100));
//PISTOLS
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + "Five Seven (I)", Material.WOOD_SPADE, 1),
ChestType.Gun).setRarity(90).setMinZone(0).setMaxZone(3));
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + "M1911 (II)", Material.STONE_SPADE, 1),
ChestType.Gun).setRarity(80).setMinZone(3).setMaxZone(4));
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + ".44 Magnum (III)", Material.IRON_SPADE, 1),
ChestType.Gun).setRarity(40).setMinZone(4).setMaxZone(100));
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + "Desert Eagle (IV)", Material.DIAMOND_SPADE, 1),
ChestType.Gun).setRarity(20).setMinZone(5).setMaxZone(100));
//SNIPERS
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + "Dragunov (I)", Material.WOOD_AXE, 1),
ChestType.Gun).setRarity(20).setMinZone(3).setMaxZone(100));
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + "M40A3 (II)", Material.STONE_AXE, 1),
ChestType.Gun).setRarity(15).setMinZone(4).setMaxZone(100));
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + "MSR (III)", Material.IRON_AXE, 1),
ChestType.Gun).setRarity(10).setMinZone(5).setMaxZone(100));
this.myItems.add(new ChestItem(Util.getNamedItemStack(ChatColor.YELLOW + "Barrett 50cal (IV)", Material.DIAMOND_AXE, 1),
ChestType.Gun).setRarity(5).setMinZone(6).setMaxZone(100));

This was really useful to me, but I would like to know, what does .setRarity (5) mean?
Obviously the higher the rarity number the more common it is, but how does this actually work? Is it a 5% chance to find it? Or is it some other system?

 

Would @Mario know?

 

But isn't there only one item per tier and category? For example:

Category: Sniper
Tier: IV

The only item in that selection is a barret.

 

So... the possible guns for Zone 5 are:

Dragunov: Rarity 20
AWP: Rarity 15
MSR: Rarity 10
Magnum: Rarity 40
Desert Eagle: Rarity 20
M1014: Rarity 20
Spas-12: Rarity 10
Uzi: Rarity 40
UMP-45: Rarity 20
P90: Rarity 10
M16: Rarity 40
M4A1: Rarity 20
AK47: Rarity 10

Total Rarity: 275

AK-47 Rarity is 10. So am I right in saying that if you WERE to get a gun in a chest in a Zone 5 town, you would have a 3.6% chance to get an AK-47? 100 divided by 27.5=3.6 approximately

But, the question still remains, what is the chance of getting a gun as opposed to food or armor or bandages?

 

And these all have equal chances? And is the thing about AK-47 having 3.6% chance to spawn that I posted above correct?

 

Cool. Thanks a lot, this really helped! We have cracked the code to WarZ chests

Another question to this topic, what is the .setRarity of diamond armor? Also, what else is in the Industrial category, other than armor?