Bore fouling question..

[Ken14]

Here is an interesting one for you all....I have a Weatherby Vanguard in .308..24" tube. After a through cleaning, it takes 6 shots or so for it to shoot where it is sighted in at. The balance of my rifles shoot where they are supposed to after 1 fouling shot, EXCEPT this one. Any ideas..?? Its is fairly new, less than 200 rounds thru it.

All input is appreciated.