I will describe the best case scenario, which is why this build would be potentially powerful:
Under 20% life.
+54% crit chance.
+50% crit damage.
-82.5% damage taken.
+50% life steal.
Now this is all before gear is taken into consideration. To finish the example, I have to assume maximum frenzy is either 75 or 100.
Weapon toss for 1593%-1998% weapon damage to target and all targets within 22 yards.
With crit factored in, assuming 2x crits are normal, average damage per target is 3409%-4276% weapon damage average to all targets.
With 50% life steal, I can pretty much guarantee that's a full heal. Way overkill, but that means with only half fury you could still do an average of 2110%-2542% weapon damage. If you hit 5 targets, you heal yourself for ~5815% of your weapon damage.
I may have messed up on some of the math depending on how things multiply or add together, but regardless the combination of effects would be powerful under 20% hp, and when the stars align like this, the damage would be astronomical. edit: fixed the math I think.
Hopefully from a balance perspective, these numbers are higher than the reality, but I don't currently see why they would be. This would require 2 procs (revenge and overpower), fully stacked bash (easy enough to maintain), use of ignore pain (if you want 50% leech instead of 10%, probably excessive, but worth using to stay alive until you throw), and most impotantly, a corpse nearby (i think). This is by no means a ranged build, it's just using a combination of effects to perform a devastatingly powerful aoe attack that would potentially fully heal you, with no cooldown, as long as you're under 20% health.