Anyone know how naval gun nomenclature works? For example, with small arms when we refer to a "calber" we are talking about a multiple of an inch eg. .50 cal = ½" bore diameter; .22 cal = .22" bore diameter etc. As for naval guns there are/were 16"/50 guns which are called 16 inch 50 caliber guns. I'm fairly confident that the 16" refers to the bore diameter so the question would be about the 50 caliber part of it. I do have a theory but I thought someone might know for sure. Anyone?