The weapon, along with the rest of the mod, was originally revealed on the official Counter-Strike website back when it was still hosted at Planet Half-Life.
The weapon was given a description: "Exceptional accuracy (as expected from the Sig line of firearms) can be found in the SSG-3000 bolt action sniper rifle. Used by many European counter-terrorist units, the SSG-3000 is capable of blowing a man's head clean off (e.g. Dirty Harry movies)."
The weapon was replaced by the G3/SG-1 before the first beta had been released, thus the weapon was dropped from the game.