Board Thread:Off Topic/@comment-25396609-20160319212213/@comment-25396609-20160320055653

simplest option would be palm firing, but flipping open at the wrist or popping out of the forearm would also work.

The advantage of using metalstorm technology is how lightweight the systems are, you literally just have the barrel, bullets, and a simple computer that controls firing.

see, most of a guns weight is in the frame and mechanical components, the frame is the arm itself so there's no worry about that, and mechanical components for the gun are all but eliminated.

the weight of the bullets is negligible, since they are caseless and use a more compact propellant.

so, overall, you have maybe 1/2 pound of bullets per barrel, and 1/2 pound of steel for the barrel. you can comfortably fit up to 6 barrels  in a standard forearm depending on caliber, and the weight would be about the same as a natural arm.