When it comes to Olympic shooting, champs don’t get a free pass. Sgts. Vincent Hancock and Glenn Eller, reigning gold medalists in skeet and double trap, respectively, will have to qualify for the 2012 team this week in Tucson, Ariz. USA Shooting has previews of the skeet and trap events, which will run through the weekend. Staff. Sgt. Josh Richmond, the 2012 World Cup double trap champ, already has a spot locked up for London (read more about the World Cup win here). Sgt. Jeff Holguin, another 2008 Olympic team member and the 2011 national double trap champion, will compete…