I switch to the shotty in CQC. Also, with the Hunter you have throwing knives so if they're close but not close enough to melee you can hit em with that too.
I just dropped a vid montage doing work with that class. I haven't even used an AR in this game yet. Only been using the scout rifle, shotty sniper and whatever heavy gun I have on me. You could also pick the LMG as your heavy weapon if you're concerned about close encounters... you just have to keep an eye out of the ammo drops.
yea I rock with that burst and hand cannon. I got the LMG but I am always miles away from the ammo crate when it spawns.