I talked to the people at Federal one year about their brass. They said that the brass drawn for their 6.5x55 is the same as that drawn for their 308 and similar sized cases. There are some dimensional differences but it was the same metallurgic composition. It was more cost effective to just run the same mix. I don't know if that was true then, and if so, I don't know if that holds water now. Just an FYI.~Muir