User blog comment:USS Enterprise CVN-65/The New (And Improved) Official Roleplay Room/@comment-10905876-20150910160204/@comment-25584152-20150912001146

/facepalm

Can you not convert cm to inches?

If so then here's most naval gun sizes.

10.5=4in

12.7cm=5in

15.5cm=6in

20.3cm=8in

30.5cm=12in

35.5cm=14in

38cm=15in

40.5cm=16

45.5cm=18in

53cm=21in