Did somebody say "short round" or pot shot?
Levelhead - a 30 degree heel on a sailing vessel is pretty extrem and is not common at all except in some pretty heavy weather, FWIW. IIRC, shot was usualy stowed in crates, hauled on deck with the charges by the 'powder monkey', as needed.
nine yards = length of machinegun ammo belts for WW2 fighter planes, i.e. emptied the gun into the target