I have a MH10 ION Cannon, x2 damage (fire). Here is a short video showing stats and damage. Notice I’m only wearing a Transformer shield and the target receives 1 million damage. No character mods or artifacts and I’m at 1 million damage.
What glares out to me is that it has a mag size of 6 but requires 7 ammo to fire it.
It would be funny if it didnt fire unless you had a mag size buff on a COM or artifact on.
oh the damage if that were 90/300