I have decided on just about everything else on my 308 build, but one of the most important. Barrel length. I'm going to be using it for F-class, but also other types of shooting; maybe on occasion hunting if I feel the urge to carry an 18 lb. rifle around. I've shot GAP crusader's with 23" barrels, and really liked the feel of those. What would be like a minimum barrel length to keep a 175 supersonic to 1k or just a hair past it with a Varget like burn rate powder? I'm looking at a Bartlein, and the blank will come at 29" with a 1in10, but I highly doubt I'll keep it at 29.