A `.mul` records what is in every critical slot, and MegaMek reads those back: a magazine whose `type` names acid rounds is loaded with acid rounds and scored as such. helm read the design's own slots and answered as though nothing had been touched - a Shadow Hawk with acid rounds is 1,069 and helm said 1,064. `bridge/DumpMul.java` is the oracle, and the first one that reads a file rather than shooting a design itself.