Lack of ammo

You need to do something about ammo. There needs to be someway of you getting your own resupply without relying on team mates.

So many times I've been in games now and hitting LB and requesting ammo doesn't get any one to drop ammo. Speaking on my mic doesn't seem to get anyone to drop any either. 

So many people using the support class just don't fulfill there role and it's so frustrating. In turn I don't enjoy the game. I know that's not really the games fault players don't know how or choose not to work as a team.