Yesterday I was cleaning my O/U barrel and I looked down the barrel from the breech end and could see a streak just past the porting in both barrels. When I turned it around I could see that it was fouling in the choke tubes(both). It was directly in line with the ports. I shoot the unsingle barrel much, much more and can find no trace of this. The chokes are Briley, flush in the O/U and exended in the unsingle. Have any of you experienced anything similar? I am using the same reloads in both barrels. Claydot , 1 1/8 magnum, Downrange XL 1 1/8 wads. Comments(useful) please.