The Ammo Rework as been out for some times now. And this rework have an huge impact on Weapon like [Kuva Bramma], [Lenz] ect.. Low skill weapon in general as been nerf in the good way : the Ammunition and capacity to handle the spam. Actually, they cannot if don't use [Carrier] and it's refill ammo mod and an Ammo Mutation in the exilus of these weapon.
So this is my re"build" for the Lenz with a Simple Riven Critatis.
Against Grineer :
Swap Bane of Infested for Grineer.
And go for Corrosive or Viral + HM if don't have armor strip in your team.
Against Corpus :
Swap Bane of Infested for Corpus.
Swap Primed Cryo Round for Hammer Shot. And replace Vital Sense for Malignant Force. And that it's.
against Infested :
Actual build.