I think you might consider building a bolt rig that you could use from the bench and from field positions. They may let you use it at their F-Class matches if you ask (If you wanted to shoot F).
You might consider a 6 Dasher, 6XC, 6 BRA, or even stay with a fast twist 22-250AI. I think it will shoot good at any of those distances, if it is built right.
Even a fast twist 223 work pretty good at distance if the conditions are not to switchy.