Bullet penatration
Certian bullet penatrate weaker surfaces. Maybe you can add ammo mods. Take for examole your barret .50, or behemoth .50, the .50 BMG round is made to penetrate tank armor, so say you somehow locate where the player is inside of a tank, the barret will be able to penatrate the armor and kill them through the tank.
If i can, may i suggest a kar98 for the sniper class, or maybe even a whole forefront ww2 spinoff. Thank ypu for reading.