Doubletap was the first to load full power 10mm like Underwood does and Swampfox did. Of course we know what doubletap did to their customers with the power levels and is now trying to get their customer base back from Underwood with hotter loads these days. The point I'm trying to make is Doubletap has always used Nickel plated cases and I've read opinions of reloaders on this forum that DT's caseings are the best quality for reloading with plated caseings. So nickel is not so unusual for 10mm.