Can't understand why they fitted two different 3 inch guns.
Frankly nor can I, they just did. To complicate matters even more the RCN between 1950 and 1965 had the following guns in service
4.5"/45 Mk. 5 single mounting (HMCS Sioux)
4"/45 Mk. XVI twin mounting (Tribal class like HMCS Haida, and Type 15 frigates like HMCS Crescent)
3"/50 of American origin (Tribal class and the 'Cadillacs' as well as Type 15 frigates)
3"/70 Vickers mounting in Restigouche class and later the Mackenzie class.
In fact a logistics nightmare.
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Thank you Kim for the crest
"Never fear to try on something new. Remember that the Titanic was built by professionals, and the Ark by an amateur"