Folks have been asking for a proper 17HMR bore guide that protects the chamber and keeps cleaning solvents out of the action. I think I developed just such a bore guide
http://www.rvbprecision.com/shooting/bore-guide-for-the-17hmr-rifle.html
http://www.rvbprecision.com/shooting/bore-guide-for-the-17hmr-rifle.html