I just got directed to this order by a Marine here that used to work on the Marksmanship Training Unit, Weapons Training Battalion, Marine Corps Development and Education Command. I believe this is what you are talking about. The sergeant told me you have to be great at your job as an armorer and be really good on the range. Good enough to get selected to the rifle and pistol competition teams.
http://www.google.com/url?sa=t&rct=j...8kw&cad=rja