hmmm yes ik of both the 5"/25 however i read was more AA gun than dual purpose but i guess u could make a dual purpose mount with it
It could depress to at least -10 degrees and fire armour piercing and HE. That makes it a dual purpose gun per definition.
and while the 4in. is excellant i feel its a little week for a destroyer i should have specified that
thankyou very much everyone for these insights any others would be much appreciated
AFAIK, as far as the Western navies goes that's it for prewar DP guns, aside from the 5"/38 and the various 4.7" guns. I think the Japanese had some as well, but I'm not sure.
Indeed the Japanese had the twin 5" mounting on their Fubuki class destroyers (Special Type). That mounting had 70 degrees elevation, so it could be called Dual Purpose. Later classes of the IJN destroyers had a simpler mounting, offering only 50 degrees elevation.
The Americans did not consider the 5"/25 a Dual Purpose gun as the muzzle velocity of the gun was considered too low for penetrating any sort of light Armour, hence the move to the 5"/38, which was a middle way between the surface only 5"/51 and the AA only 5"/25.
The Royal Navy was in fact unable to produce a true Dual Purpose mounting for destroyers until near the end of WW2, as the 4.7"/45 twin mounting, like these on the Tribal class and J and K and N classes had only 40 degrees elevation, and the twin 4.7"/50 mounting (in fact more like a turret, albeit unarmored) had 50 degrees of elevation. These are not fit for AA work, only for long range barrage fire against enemy planes like torpedo bombers (which usually wee coming in low) or level bombers, that when are far are seem to be low. Also remember that the Royal Navy had great faith in torpedo bombers against shipping, and until the Spanish Civil War didn't consider dive bombing as a threat to warships.
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Thank you Kim for the crest
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