Jackie Schmidt, posting on Benchrest Central, observed that there may have been some production changes with Lapua 220 Russian brass. This brass is commonly used as the parent case for fire-forming 6 PPC cases. The newer 220 Russian brass has slightly thicker neckwalls, and, according to Jackie, the new brass is more consistent in overall neckwall thickness.
01 « June « 2011 « Daily Bulletin
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