I have just put in the stats into nfcalc and played around with its "simulator" to find the classing.
The sailors seem to have a base of 10 accuracy and 12 reload, left armament sailors until around lvl 62 and then classed to Chief DP gunners. I say "seem" as nfcalc also has its errors.
They look fine to me, according to what people have been recommending for IJN AA:
- leave them armament sailors until Yamato levels, then class to Chief DP
- leave them armament sailors until lvl 62, then class to Chief DP. The missing reload displayed ability will be offset by the more recruits gained (armament sailor 6 recruits/lvl, Chief DP 9 recruits/lvl).
At the moment, the better one of your gunners has around 1239000 reload true ability, roughly half of what is needed for the reload cap.
With all the vet packs that you surely have won over this last event, get them to 109 vets each. Wait for a good vet conversion rate and up the vets to 149 I'd say (you need premium for that). With those vets, full experts and at lvl 100, their reload true ability should be at around 2280000, not too far away from the reload cap.