A lot of people have been asking about sizing, how to approach it, do I cam over, smash the shell holder to the bottom of the sizing die, do I use a case gauge, etc.
I think this method really cuts to the core of what we're trying to do with sizing, namely where we're placing the shoulder so we get consistent headspace that will actually fit in the chamber and allow the bolt to lock over the reloaded cartridge. For the 6mm PPC family and its .350" datum line on the center of the shoulder per SAAMI, we use the .350 bushing provided by Hornady in the kit.
I thought some pics of how the process works would be worth a thousand words:
Bushing installed in my calipers, indicated to 0.000" off the 2" mark, which is the length the tool will fill between the blades after being installed.
L-R: Unfired AA 123gr Scenar load, 1x fired Lapua brass, reloaded cartridge with enough shoulder setback to chamber and lock-up
Unfired Lapua brassed cartridge headspace measurement: 1.205"
Fired Lapua brass, unsized headspace measurement: 1.218"
Sized to fit and lock-up in my chambers with a bolt that has the ejector removed: 1.210" (I can get away with 1.212" and still lock up, so this is a little excessive sized back .008")
I think this method really cuts to the core of what we're trying to do with sizing, namely where we're placing the shoulder so we get consistent headspace that will actually fit in the chamber and allow the bolt to lock over the reloaded cartridge. For the 6mm PPC family and its .350" datum line on the center of the shoulder per SAAMI, we use the .350 bushing provided by Hornady in the kit.
I thought some pics of how the process works would be worth a thousand words:
Bushing installed in my calipers, indicated to 0.000" off the 2" mark, which is the length the tool will fill between the blades after being installed.
L-R: Unfired AA 123gr Scenar load, 1x fired Lapua brass, reloaded cartridge with enough shoulder setback to chamber and lock-up
Unfired Lapua brassed cartridge headspace measurement: 1.205"
Fired Lapua brass, unsized headspace measurement: 1.218"
Sized to fit and lock-up in my chambers with a bolt that has the ejector removed: 1.210" (I can get away with 1.212" and still lock up, so this is a little excessive sized back .008")
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