I always shoot a couple of fouling shots after cleaning the bore, but the fouling shots are always dead on or very close on all my rifles (all with after market barrels). And they all shoot great with a dirty bore until the bore gets too dirty, which varies with the rifle. It would worry me if fouling shots were far away from normal. I need to be confident on the long shots.
the last 3 shots i shot today landed in a group that mic'd .787 inches at 200 yards. an inch under the X the only thing that makes any sense is that it doesnt like a clean barrel.