Also, klagldsf, how the bleeding zogg do you manage to make a semi-automatic 6" gun fire 20 rpm?
Believe it or not, that's the qualified RoF for the
6/50 QF that the British used on their last gun-cruisers. Of course that's with the qualification of the barrels becoming very hot, and that's probably really pushing the limits on my design considering that the caliber has been increased to 57.