The barrel on my 308 is about shot out and I'm considering going with a McGowen pre-fit barrel in 6BRX. While I've swapped out barrels on Savages before I've never done it with a "wildcat" cartridge. What if any challenges can I expect? Also, who makes go, no-go gauges in 6BRX? I was under the impression that PT&G did but I don't see them listed.