Thinking about getting a new prefit barrel for a Savage build, and after spending many hours on this website and contemplating many calibers I think I've narrowed it down to these two. Big draw to these is no fire forming of brass, efficiency, and relative lack of recoil. Intended use: paper, steel, and possibly varmints to 600yd. My research has left me with a few questions I was hoping those with experience using these calibers can help with: 1. 6XC Norma brass through SSS is a bit cheaper than 6BR Lapua brass - is the XC brass as durable as the Lapua cases? 2. I know what the cartridge pages say...but what kind of velocity increase over the BR might I realistically see from the XC? 3. How much barrel life does the XC give up to the BR? Thanks for the input!