Hi Fred:
As usual you bring a great deal of technical expertise in the working of metal to the forums. The ONE issue I would like to see addressed is:
"What was the purpose of the joining seam if it wasn't used to size rings die cast from flat stock?"
Please note the no one has come up with a reasonable or any explaination since my original post. I continue to maintain that Don Boyle,Gaspare and many others here are right in their assumption these rings were originally die cast and have seen nothing posted to refute this.
