This mod requires https://www.curseforge.com/minecraft/mc-mods/a-v-a-in-minecraft/files
Show case:
https://www.youtube.com/watch?v=nWY3OZxOY8k (Old)
https://www.youtube.com/watch?v=83KahuUndso (New)
Choose different attachments on your gun!
The durability bar is the maintenance of the gun, as is the efficiency of some of the stats.
For example I have a gun that has durability 90 / 100, it means my accuracy, stability..etc is 90% efficient. Every shot has xx% (varies according to the capacity, (1000 / capacity)%) to decrease 1 durability, and different attachments give different quantity of durability,