For accuracy, Lapua is hard to beat. It is dimensionally much tighter than most other brands and its durability is excellent. The PP may or may not handle reloading well. I've heard mixed reviews of it in other chamberings, so I don't know what to tell you to expect from it in the .338, specifically. If it's cheap enough, all you can do it try. If the results are unsatisfactory or you are wanting top precision long range loads, Lapua would be what I would invest in.
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