Hello lancaster,
Thanks for the reply.

When I fire-formed the 30-06 brass I wrapped with a single layer of tape at the head. All went well.

Today I had one of the modified 5.6x61R cases "bow out" at the extractor groove. I cut-off the rim, but made too wide an extractor groove, and too much bevel. I found a source for custom brass called Robertson Cartridge Co. (RCC). 60 pieces of brass will cost $375 USD delivered. That comes to $6.25 each - ouch!