MG Specialist Ogryn (Twin-linked Stubber, Shovel)
 Ogryn Build - Warhammer 40k: Darktide 

Surprisingly fun and effective build I saw in some YT video and then adapted to my preferences. In particular, I sacrificed some range and blitz talents to make its melee stronger - as you can't rely on range attacks on higher difficulties (not if you play in PUGs at least) like the original build was. You also can make its melee way more powerful if you'll swap Shovel for Pickaxe - but I like the Shovel for ease of use and speed of accessing it, and I'm kinda bored of Pickaxe too :D

I've tried it up to most of Auric's difficulties (barring the Maelstrom) and Havocs up to lv20 - and it survived it all consistently.

Tips:

1. Use the shovel whenever possible to save ammo, mutants can be one-hit with it if you switch it into anti-armor mode and charge your heavy attack long enough; use the Stubber in braced mode (alt attack) to kill specialists (it's surprisingly effective at this, even at a distance) and remove huge mixed hoards; finding the right melee/range ratio is paramount to use this build well in higher difficulties, use the gun too much and you'll run out of ammo when you need it, use it too little and attrition becomes unmanageable in a long run, as this build isn't particularly strong in melee
2. If distance allows, start shooting at approaching hoard from afar without activating your ability at first; let them come closer, then activate your ability to instantly reload your gun and apply a bunch of burst damage; this allows you to dish out damage for much longer periods of time; whenever possible go into bracing mode when shooting, besides allowing for higher accuracy it also replenishes your toughness thanks to Steady Grip and gives you extra t.dmg resist thanks to Mobile Emplacement
3. Note that blesses on the gun reward continuous fire handsomely, especially when directed at a single target - what comes in handy in boss fights, I rarely see anybody topping me in terms of boss damage in PUGs; avoiding interruptions becomes easier with some practice and planning
4. You don't have to always reload if your gun is empty, as activating ability will do it for you anyway; still, I try to always keep at least 30-50 rounds in the gun, to be ready to take out a sudden specialist