Bro unlock the Elite Bodycount gamemode and grind exp there with the veteran which increases your exp at 100% trust me bro i can like grind a class up to tier 1 in just a few hours with it just make sure to do a difficulty you can complete and your good.
Bro unlock the Elite Bodycount gamemode and grind exp there with the veteran which increases your exp at 100% trust me bro i can like grind a class up to tier 1 in just a few hours with it just make sure to do a difficulty you can complete and your good.