I shot another series of groups today with a cold dirty barrel (probably 30 rounds through it). At 100 yards, the first bullet was 2 to 3 inches high and dead on center, the next one was about where it should be and a little off center and the next three were one ragged hole (much less than 1 MOA) right where they belonged. Two to 3 inches high on the first shot with a cold barrel is usable. If the gun were less accurate, it's something I probably wouldn't have noticed.
I've been working with Barnes bullets and cleaned the barrel quite aggressively with the Barnes bore cleaner, multiple patches, etc. in an effort to make them shoot accurately (as Barnes recommends). This may have been my problem; an overly clean barrel. Barnes says their bullets are softer than regular bullets and need to be shot from a clean bore to be accurate. I think that is probably true. I very much like the way Barnes bullets perform on game but I'm not enthralled with fussy bullets. I think I'd rather shoot accurate bullets that would shoot well from a dirty bore in a hunting situation.