I've been trying to build a turret which I have been able to build successfully before, a 4000 module cannon/cannon/punch. I am generating 195K power in the gun housing and 235K power in the turret base. Both the turret housing and the base have ~150K of power storage, more than adequate for a few firings of the weapon. The weapon should be drawing 405K power, well within the generation capacity of the housing and base. The game hud even 'says' that's what it is drawing. Yet when I test fire the weapon, it rapidly depletes it's battery and stops firing with a power failure message. Even if I add several million power storage with extra capacitors, it still runs out of power. If I dock the turret to a million power regen source, it is able to maintain fire with it's batteries at a constant 79% without the additional batteries. It appears that the gun IS inheriting power, yet despite the barrel and base haaving more than adequate power on their own, somehow the weapon is still running out of power when not docked to a massive external source.

I've included a zip of the blueprint directory in the 'steps to reproduce'.