DISCLAIMER: The Riven displayed in this build is the exception, not the rule.
The build also lists Blast among its damage types. Overframe is drunk and doesn't know what it's talking about.
Use Thermite Rounds/Hellfire if you don't have a Riven.
[Hunter Munitions] is present due to the high crit chance of this Kitgun, coupled with the fact that Viral boosts Slash proc damage by a fairly high amount.
Heat - obviously - is for armor stripping.
Shields are covered by the innate Impact of the Kitgun.
Pax Charge converts this into an infinite ammo Kitgun and shortens the ammo recharge rate considerably.
Charge for best effect against groups, or tapfire against heavies.
Firerate of some sort is strongly recommended due to the disgustingly long charge time on this Kitgun.
I would suggest replacing [Vital Sense] with firerate if you don't have a Riven, or your Riven doesn't have firerate on it.