5-8% toughness on Chained Hit.
Hitting at least 3 enemies with an attack, restores 12-15% toughness.
5-6.5% Strength for 3.5s on Close Range Kill.
2-5 bullets loaded from Reserve on Critical Hit.
Stubber is main spam when ammo economy allows (vet, psyker, etc.). It's bad at Carapace, so use the hammer for that and for hordes when ranged is not needed or viable in the scenario.