Hitting at least 3 enemies with an attack, increases your damage by 24-36% for 3 seconds.
Hitting at least 3 enemies with an attack, increases your cleave by 140-200% for 2 seconds.
+4.5-6% Close Range damage on Repeated Hit. Stacks 5 times.
+7-10% Reload Speed for 2.5 seconds after Close Kill. Stacks 5 times.
Speedload, raking fire or fire frenzy are all good additions to Dumdum on the columnus.