Sniper rifles are just as important here as any other weapon. The M1A rifle is considered by most to be the best sniper rifle in the game.
Of course, you will need to find a scope for it and maybe even a bigger magazine to make it so much more effective. But this high-end sniper rifle has a huge damage output and a really high fire rate for a rifle of this type.
But the best part is the hit range that reaches up to 60-70m and beyond, which is incredible. If you like to take out your enemies from afar, then this would be the best choice for you.