(adsbygoogle = window.adsbygoogle || []).push({}); Step 1: Goto Squad mode, Choose Wargames, You can pick any difficulty exp is all the same.
Step 2: Play the match til you get Max XP Reached, Then Leave the Game.
Step 3: Repeat

Not sure if they are gonna patch this or not, but it's not cheating so...

Not patched and you realize that this is 2/3 times less XP than in public matches ?