I must be missing something on how to take down these mongrels. I've tried several things but in the end I have to just use attrition to get them to the damage induced stun. I've tried 5-stacking mines (figured something like Mkolls tactic would work), grenades at their feet, running and gunning, and straight melee with dodging. Dodging is apparently hard because even some times I still get minor damage from his attacks. I thought I had read that you could induce a stun attack on them, but so far I have only gotten the damage induced stuns. I am playing on Normal.
On melee, I can barely get 2 strikes in before his delivery. Should I be initiating two empty swings before my last two (with the heavy strike) get close enough to him?