Sand Slag (present working title) is a game set some time in the distant future. The human race has ventured through space for some time now, but never gone to far. A need for new land to house the massive population has called the forces in power to make a decision to expand well beyond the few solar systems presently inhabited and colonize new systems deep within the galaxy. A massive fleet is constructed. An array of varied ships for their varied purposes are created to create a self-sustaining environment for the inevitable long voyage through the galaxy. Many years pass as the voyage is underway, everything was fine until this first fleet neared the inner ring of the galaxy. Mankind knew they weren't alone, they ran into many alien races before this, even far superior races, but nothing prepared them for what was to come.
Here is a reusable missile rack concept. The gold bar is a possible attachment point (thinking about redesigning it). It could also provide a mech with arms the opportunity to pick it up as a weapon, fire all the rounds provided and then drop it to pick up another weapon.
Again as you can see the tubes are hexagonal. The tube covers will pop open, the rocket will fly out, and the cover will resettle. This will provide the nano-tech within the rack to replenish the ammo should someone have the adequate resources to do so.