Creating Multiple Copies of weapons based on ammo level?

[Raziel236]

Hi, at the moment I'm trying to create multiple versions of a weapon based on how much ammo you have at the time so that the weapon's appearance changes multiple times according to different ammo levels.
At first I thought about using JumpifInventory but then I realised it wouldn't account for the firing states as well. So then I thought i'd use sister weapon but apparently you can only create one of these and they are only for PowerWeaponLevel2, so what is my best method of approach for this? Any pointers rather than spoonfeeding would be great as I'd like to learn myself.