Eric,
Your question is pretty complex and there is not just a simple "yes/no" answer.
You can see this by visiting the variety of cleaning rods Chuck Whittaker has posted on his Land of Borchardt web site.
http://www.landofborchardt.com/
Also, if you do not have this book...Bender covers cleaning rods in some detail as well in his big book...showing varieties and materials used :
http://www.simpsonltd.com/product_in...oducts_id=2630