hounddawg, If the rifles chamber is headspaced at 1.5713" maximum & the brass is sized to the minimum of 1.5575" this gives head to datum slop of .0138"
Brass will separate using these SAAMI measurements. Be careful how you headspace that barrel. http://www.saami.org/PubResources/CC...04%20Ruger.pdf
I am not a gunsmith, i hope you are.