I built one in 6.5 Grendel and I would do it again in a heartbeat. Mine is built for long range, not hunting. With a 26" barrel it's just too heavy to cart around. Beyond that though it is a wonderful gun/caliber. I've only been able to play out to 300 yards, but it will keep them all in a 1" circle. Unless reloading there isn't much variety out there in loaded ammo, but you load so not an issue. If only I could take it deer hunting and not just punching paper I'd be totally happy.
Thanks for the info! I was thinking a 20"barrel... After reading up on it, the 6.5 may be the best choice.