The Daily Star think the Navy’s new five-inch gun is only five inches long
— Alistair Coleman (@alistaircoleman) July 29, 2016
The five inch bit actually refers to the calibre, or internal diameter of the barrel, not the length.
— UK Defence Journal (@UKDefJournal) July 29, 2016
The story has since been corrected and rewritten to make guns sound like a really good thing. Yay!