As a habit I always run new brass through my FL die just make sure that everything is right even with the Lapua brass which generaly I could have just loaded them.
I also use a VLD chamfer tool on the case mouth.
I have never had to trim lapaua cases to make sure that they were all the same.
Those 300 win cases are expensive but they will las a long time and unless you get crazy with the pressure 100 will probably outlast your barrel , especialy if you re-anneal the necks as that is generaly what happens first , cracked necks after about 8-10 sizings.
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