The solution is simple.Clean your barrel and fire a group.Then let the barrel cool and fire another group.If both groups have the same point of impact and are of equal size it won' t matter if you hunt with a clean or fouled barrel.If the point of impact is different hunt with the barrel in the condition that it was sighted in.My own hunting rifles will shoot the first three shots out of a clean barrel into 1/2" and the next three shot group to the same point of impact as the first group.As a result I usually hunt with a clean barrel.