After only a couple of firings, I am seeing split necks and cracks in the shoulder from a new batch of Lapua 6mm BR brass. This is new brass, came in a plastic box as opposed to their old cardboard box. Lot number is P00487801. Never had any problems with previous Lapua brass. The problems are present regardless of sizing method...Full Length (Redding Dies) or Neck Sizing (Wilson). Case necks were not turned, I have a .272 neck in the chamber. Have been shooting relatively lite loads, first 29.0 grains, then 28.0 grns, H322. The bullet is seated short of the rifling, a 68 grn Berger. In short, all was fine till this last batch of brass. Anyone have any ideas...or did Lapua's quality just slip on this batch. Case neck thickness on the old brass averaged about .013. The new troublesome brass had a neck wall thickness averaging .012. Several cases were measured, they definitely have changed their production specs.