Replace Polar Magazine with Automatic Trigger if you prefer higher DPS on your auto-fire mode.
[Polar Magazine] will greatly increase the damage output of your charge attack while sacrificing sustained DPS on your primary fire.
Automatic Trigger:
Auto-Fire Sustained DPS: 121,922.2
Charge Fire Sustained DPS: 810,466.5
Polar Magazine:
Auto-Fire Sustained DPS: 111,294.0 (-8.72%)
Charge Fire Sustained DPS: 1,096,513.5 (+35.29%)
You gain more than you lose with [Polar Magazine], however the choice is ultimately yours.
You can use both builds with the same Forma polarities.
If you're using Automatic Trigger, move the V-Polarity from [Hollowed Bullets] to [Automatic Trigger].