No.
you cant upgrade it twice
It means you can upgrade your guns.
disco stick
You get more maximum ammo when you upgrade the gun. The ak74u usually has 20 ammo, and gets 40 when its upgraded.
No, you can't upgrade a gun more than once.
In Call of Duty: Black Ops Zombies, upgrading ammo at the Pack-a-Punch machine costs 5,000 points. This allows players to enhance their weapons with increased damage and additional features. Players can also upgrade their weapons multiple times, but the cost remains the same for each upgrade.
Makes your gun stronger, makes your maximum ammo more, can add an underbarrel.
To upgrade the Wind Staff in Call of Duty: Black Ops 2 Zombies on the map Origins, you need to complete several steps. First, collect the Wind Staff parts and build the staff at the excavation site. Next, you must charge the staff by killing zombies in front of the wind generator near the spawn area to fill it with souls. Finally, place the staff in the pedestal located in the church, and complete the corresponding challenge to upgrade the Wind Staff to its more powerful version.
it should
you upgrade the ammo by pack a punching your weapon it should costs $5000 to pack a punch which will upgrade your weapon and ammunition
Black Ops 2 Zombies is harder but also way funner than Black Ops Zombies.