I happen to like [Bonewidow] over [Voidrig]. shit can't die, and you're not stuck immobile in guard mode, but you got a decent sword. the build probably ends up whatever mods you have, cus its not really practical to spend the plat, forma, and years off your life to level this 6 times.

[Ironbride] will do more damage than 99% of archguns, though i think not as much as [Arquebex] technically. Playstyle is just alternate between meathook and shield to stay alive, swing big metal bar, and maybe press 3 if you feel like it. Should be good to survive easily up to level 200 ish. you can also punch with the shield, but idk what its useful for over swinging.

Nechramech [Fury] does affect [Ironbride], and nechramech [Rage] should give you near infinite energy and keep [Ironbride] up, though if you shield or use endurance strats and don't take health damage a lot, it may not be consistent.

Nechramech augur may be good, but I don't have it and don't feel like getting it to test.