I don't have any mechs that run HMG's, but this Firestorm seems like a nice platform for it. You have to take the engine rating down from max slightly, but it doesn't hurt it too bad, the build works out very nicely: Skill tree: https://kitlaan.gitlab.io/mwoskill/?p=jsonbin1.5c19b0e88c05c52ebaca71e8#s=Weapons Skilling it up was quite fun. Not an OP mech but can get some good work done if you apply it correctly.