You don't understand. When I say steampunk gatling guns, i don't mean steampunk gatling guns like you're thinking...
I'll just let this peice of writing detail it for me:

Four-barrels of empire-forged brass-titanium composite capable of putting out ten score bullets per minute in the direction of whatever poor fucking sod was at the other end of it. Armour-piercing, mercury-tipped, hollow points, every concievable type of ammunition could be hooked up to the spinning barrels and sent thrumming towards your enemy in a deafening drone of firepower.

Hamberly picked up the machine, the two handles smooth and polished from use, and gently rotated the barrels, before shrugging on the thirty-pound backpack that was needed. Carefully, he unrolled the length of bullets, the brass tumbling through his fingers and slotted the length into the side port, before taking aim at the dummy across from him.

A soft whirring sound started up, building in intensity until with a throaty growl he first bullets were spat forward. Each explosion propelled the intensity of the next, and the barrel started to heat, each thump heating the barrel up more and more until he sat it down, the steaming metal hissing upon contact with the damp earth, the dummy now nothing more than a few stray whisps of grass, splinters splayed across where the figure had stood.