Load Thrower
 Hive Scum Build - Warhammer 40k: Darktide 

It's not the best build in the world, but it's goofy and fun. Infinite ammo shotgun is just a hoot and a holler. 

You can also swap the combat shotty for the Double Barrel (probably actually a stronger weapon all around.)

Double barrel shotty build, (if you wanna use it) I dumped mobility, since you're ALWAYS reloading. Blessings are speedload and deathspitter. 

I basically never use melee, and the knife is just for movement and getting around, but still does well in a pinch against groups of lil guys, and push attacks against anything else. 

Rockets are for bosses and whenever a group of crushers or bulwarks come at you, because really it's the only tool for that, so you'll be needing to pick up grenade pick ups a couple times per game. 

Alternate the use of Desperado and your stimm to use one while the other is on cool down. Keeping chemical dependency stacks at max really speeds up the cooldown of Desperado.

Hit desperado after you expend all your loaded ammo to top it off so you'll have 26 shots if you go from fully loaded to completely expended after Desperado. 

The weakness is that once you spend all your ammo, it can be a slow reload, which is usually when I may find myself needing the knife, even though the goal is to use it as little as possible.