Wasn't it a Russian woman sniper who killed one of the most notorious German snipers during WWII? Thought I saw something on the History channel about this.
Sorry, I'm not familiar with this event, but it sounds interesting for sure. Women often score brilliantly in shooting competitions so I don't doubt that it could have happened.
You may be thinking of Vassily Zaitsev who killed Colonial Koning, the commander of Germany's sniper school in Stalingrad. (see movie "Enemy at the Gates"/
Zaitsev was Russia's most decorated sniper. There were some celebrated women snipers as well but the story line suggested leads me to believe you are referring to the Zaitsev-Koning showdown.