Have a barrel blank and Rem 700 action. Now looking for a master gunsmith to chamber for the 358 Winchester. I have blank loaded shells using Sierra 225gr and would like the barrel chambered to the round. Will I have to have a special reamer made to the loaded shell? Will a gunsmith be able to make the reamer? Or can a gunsmith use a match 308 reamer and machine the neck to the proper dimensions? Any suggestions on who would be qualified at this type of work. I want it as close to match as possible.