The M1 Garand was a rifle used by America in World War 2. And now you can use it against the zombies. The M1 is a semiautomatic rifle, with a 10 round clip.
It can be scoped, and given a bipod, making it a great sniper weapon.
However, it can't be suppressed, so make sure to use another suppressed gun or melee to take out nearby zombies, and then snipe with the M1 to kill hostile players, or zombies at long range.