Been trying several builds for this forsaken weapon and this one worked out pretty well:

• You can decide whether or not to install Lethal Momentum on the exilus slot but that will require additional forma.

• Viral damage + Hemorrhage combined create quite an interesting combo, just as other blast-related weapons.

• You can replace [Galvanized Shot] for [Heated Charge] to have another elemental combination. Still, I think it works better the other way.

In case you are wondering if this build can kill in Steel Path: yes, it can, but need a little bit of effort. Doesn't work quite efficiently with heavenly armored units like Grineer because of this weapon's nature. Enjoy!