Armor Bar and Value glitch when total defence passes 20

Im trying to make a map, so i wanted to added "new" armor with different amounts of defence. Using the stat.armor NBT tag, I increased the defence significantly (total defence was supost to be 50) , however when I wore all the armor pieces ONLY 3 armor bars appeared and it gave me the protection of 3 armor bars.

What I expected to happen was...:
I thought the armor bar would would increase (like with health boost or absorption) and give me the correct amount of defence

What actually happened was...:
Once the bar was past full, it just reset, and the finaly outcome was 3 armor bars

Steps to Reproduce:
1. Get a command block
2. Give your self a piece or pieces of armor that exceeds to total amount of defence (total armor value MUST be over 20)
3. I used the following commands:

/give @p minecraft:iron_helmet 1 2 {display:{Name:"Titanium Helmet"},ench:[{id:60,lvl:1}],Unbreakable:1b,AttributeModifiers:[{Slot:"head",AttributeName:"generic.armor",Name:"generic.armor",Amount:6,Operation:0,UUIDLeast:1,UUIDMost:1}]}

/give @p minecraft:iron_chestplate 1 2 {display:{Name:"Titanium Chestplate"},ench:[{id:60,lvl:1}],Unbreakable:1b,AttributeModifiers:[{Slot:"chest",AttributeName:"generic.armor",Name:"generic.armor",Amount:16,Operation:0,UUIDLeast:1,UUIDMost:1}]}

/give @p minecraft:iron_leggings 1 2 {display:{Name:"Titanium Leggings"},ench:[{id:60,lvl:1}],Unbreakable:1b,AttributeModifiers:[{Slot:"legs",AttributeName:"generic.armor",Name:"generic.armor",Amount:12,Operation:0,UUIDLeast:1,UUIDMost:1}]}

/give @p minecraft:iron_boots 1 2 {display:{Name:"Titanium Boots"},ench:[{id:60,lvl:1}],Unbreakable:1b,AttributeModifiers:[{Slot:"feet",AttributeName:"generic.armor",Name:"generic.armor",Amount:6,Operation:0,UUIDLeast:1,UUIDMost:1}]}

/give @p minecraft:shield 1 2 {display:{Name:"Titanium Shield"},ench:[{id:60,lvl:1}],Unbreakable:1b,AttributeModifiers:[{Slot:"offhand",AttributeName:"generic.armor",Name:"generic.armor",Amount:10,Operation:0,UUIDLeast:1,UUIDMost:1}]}