Can some one help me out; I'm an accountant not a gunsmith. To get a better understanding of the discussion I've looked at size, capacity, etc. of the various 7mm cases. Really, I don't have a clue as to why the 338 Norma case is superior to the 7mm RUM case. I'm trying to learn about the 7mm/338 Norma as it sounds like a great project. Any help appreciated.