[peterloo]

p.s. we can destroy the gun mount, but seems that the gun has a huge HP, it is at least as strong as the hull for a curiser.

While there is a shield, meaning that the gun can substain some fire before getting destroyed, I believe that the shock induced, the heat energy released by explosive, compounded by energy radiating from the burning hell below the gun in the cargos, make the crews unable to touch the gun, fearing the glowing gun will cause a severe burn.