When I lived in Stillwater I always just drove out to the Pawnee City Lake in Pawnee. They have a rifle range out there that is free to the public. It has a 100 yard range and is usually not too crowded. It is about a 30 minute drive from Stillwater but it beats the hell out of going down to the Cimmaron River by Ripley, Perkins, or Langston, which is what I always used to do before I found out about Pawnee.