The preference for heavier general-purpose guns leaves a distinct role for the 76 mm OTO Melara, whose very high rate of fire compensates for a smaller shell. The 105 mm gun is judged less attractive because it falls into roughly the same firing-rate category as 4-, 5-, and 6-inch weapons. If those rates are broadly similar, a 6-inch gun offers the heaviest shell in the group. A 5-inch gun can instead balance weight of fire against the magazine space needed for hundreds of rounds. On a ship of several thousand tons, the extra space for larger ammunition is judged affordable. The suggestion that only a little more hull length would be needed is an informal design judgment, without a worked magazine layout or cost estimate.
Notable Point · 25:10-26:49
Choosing between 76 mm, 5-inch and 6-inch guns
A high firing rate favors 76 mm, while comparable firing rates shift the larger-calibre choice toward shell weight and magazine capacity.