You seem to be lacking some information. Researching on how to correctly class and use sailors is highly advisable expecially when using sailors you spent time on. Here are a few things that may help.

First, none of the new nations (MN,SN,RM) offer any AA dedicated guns such as older nations (US, RN, KM or IJN). 

Second, You specify you made +12 AA Sailors so in technical terms, you classed your sailors right, Your sailors have a higher AAW defence.. If you were making the correct AA gunners you would have made them +12 reload as you would have for the older nations.

You can still use the sailors but they wouldn't be very good in the lower levels. You would need to over vet them in order to reach the cap early on. Regardless, Your sailors can still reach the cap quite easily if you make +11 reload. Around level 60, the dual 3.5s have some pretty good spread and reload.

I deleted them but thank you

8)

overall, there are only 3 dedicated aa guns in MN line the 3.5" lvl 25 and the 5.1 dual and quad AA which your main gunner can use or a pair of high rel base gunners

and you could try using some other guns that can be use as aa as well and be able to switch to HE for attacking