I can see the HUD change when a mortar is deployed in this video. Is there a way to change the HUD zoom during the game?
You have to press start. Not enough buttons. And no, you cannot remap this on a console.
On PC the keys are
I don't know the controller button equivalents for this, unfortunately!
I found this controller layout scheme
But wow, I don't see the map controls anywhere. Maybe they couldn't fit it in there? Can you remap controls on the Xbox? Perhaps there's a way to remap the map zoom/size functions to one of the existing buttons?