Of the two is there any difference? If so what is the difference? While reading other posts I'm seeing someone mention a 338 Lapua mag improved and also seeing a 338 Lapua mag AI mentioned. Are they one in the same? Also seeing an excaliber mentioned on a couple of different posts, I know it's a big boomer, I just am curious as to what case it uses and any modifications. The more I read about the 338 monsters the more I think I need one [ want one ]! Thanks for any info.