So I picked up some reloading gear at a garage sale recently, cool old square metal powder cans, manuals from the 70's etc.
Among these things is this remarkably unmarked seating die. As best I can tell it's a Hornady micrometer seating die but no markings at all, on anything (except numbers on the dial of course). Looks complete but figuring out the caliber is challenging.
My micrometer tells me the seating stem outside diameter = 6.12mm or .241 in
The inside diameter of the sleeve where the neck goes in = roughly 7.05mm or .277 in
A possible clue is the shell holder that was in the press with the die (assuming they were correct) is a RCBS #4 so maybe a magnum cartridge? But smallish neck?
Before trial end erroring thru my collection of various brass I thought I would consult the wisdom of the castboolits board for any tips or hints as to what I've got.
Picture to show details & both ends of the sleeve.
Thank you all in advance for your help.
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