If you can, try and find barrels that are reasonably new or do not have any discoloration showing excess heating. I had one barrel done that had some obvious heat discoloration and it was a PIG to do. There were hard spots in the barrel and the barrel maker who did the job (one of the best in Kanukistan) told me that the hard spots almost ruined his cutters and he had some rather unkind words. If the barrels do not have hard spots they are a dream to do. Check the barrels over closely before sending them for re-cutting from .303 to 8mm or you will not be very popular.
Information
Warning: This is a relatively older thread
This discussion is older than 360 days. Some information contained in it may no longer be current.