yup, when i'm playing with my HUNTER, equipping boots that gives more rockets, and with a rocket launcher with tripod all i got, in crucible, is 2 rockets .. if i play with my warlock, same kind of boots, same rocket launcher, i've got 3 rockets (which is the way it's supposed to be..). no one noticed that or what ?? oO
Nothing is broken. The difference here is that your warlocks launcher has field scout on it. You will need to stack another ammo perk for rocket/ hevy to get a third rocket to your hunter.