I saw too many "archon 1 shot" builds that run [Galvanized Savvy]. You do not run Savvy for those builds because you can't gain any damage from it if you have not shot the enemy first.

Archons have Alloy Armor which is weak to Radiation (75%), Cold (25%), and Puncture (15%). Weaknesses for armor are special in that they double dip in effect. First they ignore that percentage of armor, and then they increase your damage by that percentage too. So for Radiation an enemy with 100 alloy armor is treated as having 25 armor and then you also get bonus damage on top of that. That is why we use a Radiation valence [Kuva Hek] to start with and then also mod for more radiation.

Also, I advise using [Ivara] or [Zephyr] for this since [Ivara] can have a huge free Headshot multiplier on her Prowl or even a massive crit damage multiplier if you use [Empowered Quiver]'s dashwire.
[Zephyr] just gets +150% crit chance while airborne which is just enough to get this weapon above 100% crit chance.
No matter what frame you end up using I advise subsuming Roar or [Xata]'s Whisper onto them because both of these abilities are not factored by Damage Attenuation, which is the thing that's making the archon fights so shit that you're reading this guide on how to build a weapon that 1-shots them in the first place. Xata's Whisper is stronger but it shouldn't matter at this point.

Edit: I have finally gotten around to doing the math and determined that [Blaze] is in fact stronger than [Primed Chilling Grasp]. Not by that much though so feel free to use whichever you want.