We have an amazing video of a guy getting 73 Gunstreak in Call of Duty: Black Ops 2.
The video shows how to play in that map basically. He uses the Skorpion gun which has a high fire and reload rate but limited range. The result is very impressive as he goes from room to room with lightning fast reflexes cleaning out people.
The commentary is enjoyable to hear as well. He does die a bit early on but then goes in a beast mode wiping out his opponents in style with great maneuvers.
Check out the clip below.