Charlie,
I also belive the Saginaw bolts are by far the darkest. The one original I have is a original finish bavarian prison gaurd non CMP and the bolt may have been grit blastedprior to finishing, it is blued, but the top looks almost parkerized. Just my observation on my carbine. The other two Saginaw are highly polished barvaians from the CMP. They are correct flip sight guns as bought with all the fancy digits stamped all over them. Not sure of originality but not original finish.
I think the SP original finsh bolts I have had are by far the bluest of the bolts I have seen.
Just my humble opinions
Dave
