use a one piece cleaning rod, a jag, tight fitting patch and insert through a properly fitting bore guide, 2 wet patches with your favorite voodoo liquid and 4 dry patches to remove said voodoo liquid..........now the packing grease and oil has been removed and you can shoot it.....
everything that goes down your new barrel will cause wear from one degree to another, so do you want to wear it out with a cleaning rod or a bullet? the new break in instructions from all the top barrel makers now is to shoot it, anything other then a bullet down the bore voids the warranty...............