Bolter Focus - Stand and Bang
 Veteran Build - Warhammer 40k: Darktide 

This build puts accurate fire down range that can one shot any elite short of an Ogryn or Mauler and two taps those.  Devil's Claw for groaners and poxwalkers along with shredders keeps thing moving when you can't stand and bang out Bolter shots.  Chainsword can work with a cleave blessing and lacks the parry.  Use Executioner's Stance ability to quick draw the Bolter when a good firing position shows up.  Each single fire tap from the Bolter results in over five Surgical stacks if you wait for the sights to settle.  Unyielding damage instead of maniac damage results in better boss performance at the cost of rager and mutant performance.  180+ toughness and 200+ health with left side toughness regeneration on weak spot kill keeps you topped off good.  Slow fire rate means 15 stacks is impractical - 10 stacks from standing still is much easier to keep up. Surgical blessing on Bolter necessary for many one shot breakpoints, second blessing can be a flex slot.  Pinning Fire helps cleave, Puncture is good for cleanup, Inspiring Barrage a safety net, Shattering Impact helps the team vs Crushers. If you don't have a good Bolter you can use the Agripinaa slug shotgun with Full Bore blessing and two shot ragers with buck and one shot Reapers and ragers with the slugs.  This build also works good with a Shredder Autopistol with Pinning Fire and Powderburn, though you'll want a Chainsword for carapace. No Super Boxes unless you drop either weak spot damage or suppression immunity - suppression immunity is a priority in my book.