Evening Trav.
Generally I prefer to use the false shoulder method over jamming bullets into the lands, but in saying that, there is nothing wrong with jamming. I also use the longest bullets in the caliber I can get for FF.
I'd anneal the 270 cases, run them through the 280 sizer, charge the cases with a save load, seat the bullets so they'll jam into the lands and test.
Your not missing anything,
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