Introduction
If you want ranged, best possible option is Purifier class, combining Fire Strike+Inquisitor WPS skills. And Desolator have pass through attack for projectiles, making it even more valuable weapon. This is glass canon approach for this style of play.
Credit for the two previously posted Desolator builds:
[1.1.4.2] Inquisitus Deletus Criminalus - Max WPS Desolator, Ranged Fire Strike Purifier (+Bonus Flame Keeper Build) by @thejabrixone
[1.1.5.1] (2H Ranged) Let's bring BIG GUNS TO THE BATTLE - Desolator Purifier [c+] [sr+] by @afanasenkov26
Build
- pic with permanent buffs only
- now fully buffed, including Abomination and Deadly Aim
GRIM TOOLS 
https://www.grimtools.com/calc/DV99jQxV
Gear:
My goal is to have as much as possible skill points invested in FS line. So here +1 to Demo is far more valuable than +1 to Inquistor. To get the skill bonuses, I took Korvaak for the relic slot and also Demo belt. Kaisan amulet boosts both classes and gives %total damage, making it very good amulet!
Boots provides bonuses to both of this build RR skills - Censure and Mines, also stun res, DA, OA and proc. Pants to cover resistances. I like very much here the items giving +skills to FS line, Elemental Harmony rings, 2pieces Dagallon and shoulders with +4 Brimstone, together with medal, Seal of Void my WPS are sitting pretty close to 100%.
Devotions:
Abomiantion, since helm converts 50% chaos to fire, also Torch for flat damage and proc, both Kraken and Hydra, Elemental Storm for flat RR.
Performance
Build is a bit glassy, dying from time to time but if you play well and time your Displacement and passive defenses will make it somewhat consistent. Wave 169 is trouble as usual, Grava is hardest Nemesis. Also Mad Queen have nasty aura against projectile attacks, so watch out!
Times are usually under 6 minutes, with average speed of about 5:45-5:50. Here’s video - 5:26!
