Than why were they using people as ammo!? D=

But anyway, did they use guns or bows?

well warboys were crazy folk sick of some illnes. Also they worshipped V8 engines and stuff. They saw immortan Joe as some sort of God and did crazy stuff for his sake. So they could see Gates of Valhalla.

Immortan Joe had revolvers, Furiosa had pistols and sniper rifle, Kalashnikov had some automatic weapons and Bane (Hardy's version of rockatansky) had his side By side shotgun. Rictus Erectus the son of Joe. Used flamethower and large machine gun.

The gangs used both guns and bows.

Immortan Joe btw had a bard who had flamethower guitar.