Right now... and these things change like others depending on the maps, how i'm performing, etc.

Assault: L85A2 (coyote, tac light, muzzle break, angle grip), G18, Med Pack, Defibs, RGO Impacts (Combat Medic)
Engineer: MTAR (coyote, tac light, suppressor, angle grip), G18, Slams, RPG, RGO Impacts (Anti-Tank)
Support: LSAT or RPK12 (holo, magnifierx2, muzzle break, stubby grip), G18, Ammo box, C4, RGO Impacts (Defensive)
Recon: SRR61 (8x scope, variablex14, straight pull), G18, Radio Beacon, C4, RGO Impacts (Defensive)