ther is a sticky in wich you can finde some info about AAing...

cheers
Megadone

For reload classed gunners:
5.25"/50 RP 10 Mark 1 N/L/D
These guns are fairly slow compared to other nations, but have good dmg & N/L have decent
range.
Use for aimed sniping rather than walls of flak.

For AA classed gunners:
5.25"/50 RP 10 Mark 1 A
Same dmg & range as D set above, but much lighter & slightly faster.

2pdr 1.57"/39 Mark VIII (called Pom Pom's)
Now more usable since BB34AA patch, which increased range & dmg.
These allow you to put up a constant stream of small calibre flak.
Great for ripping apart waves of bombers, their limited range is for close defence,
but too short for knocking out scouts & fighters of players who closely watch their planes.

NB - for UK AA gunners, keep them as arm sailors & class late (lvl 60-90), as their reload
stat gets seriously nerfed.

Lastly, don't forget to check Trainworld for golden angles of AA guns.

These (How do i get the image to work?)



5.25 RP10 L's,better reload than the QF (or whatever guns) and still got decent
range.