You need a good small vice with nice sharp Jaws, I used a No.1 record (3"). Make sure the Jaws have a nice shape top edge, I ground mine as they were pretty bugged (thanks Flyblown for the tip). Nip up in the vice and used a course double cut file to file down just above the vice Jaws, switch to a fine file and than to 80grit sandpaper on a block for final finish.
And get a file paddle or a wire brush and keep your file clean as it will clog with lead quite quickly.
A little bit of work but I had nothing else to do today. I only shoot 7mm and 6mm so don't have much more to section .
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