In the 2 chapter I don't remember what part it is in, but in a part where there is a save point and if you keep walking you will fall of the cliff.

Run and jump and you will land on a non-visible bridge keep walking, and you will find a platform that has another save point on it.

Walk on the pipes and you will reach a place with tons of ghouls go around them and you will see a footlocker, open it and there will be a meat cannot has infinite ammo and does 300-609 damage....!