The 6-pounder has a 57 mm bore, while the 12-pounder is a 3-inch or approximately 76 mm gun in this comparison. Useful ammunition weights help explain why these sizes keep returning. Adaptability and versatility make them attractive compromises for different requirements. Continuity of calibre does not establish that historical and modern weapons are the same gun system.
Notable Point · 1:09:35-1:10:10
Why useful small-gun calibres keep returning
Ammunition weight and versatility help explain the repeated use of 57 mm and 3-inch naval gun calibres.