Bad grouping

Went to my check poi and the first 3 shots were spread out then my gun started settling in. Took a look at the barrel and there was quite a bit of lead fouling. Put gun on my holder to remove the barrel and tipped over. Then when I cleaned the barrel I accidently removed the index mark- just a helluva day!. Fortunately after some testing was able to get my barrel indexed then was able to rezero her. Just have to remember to check where the index mark is before removing barrel and not clean it off when cleaning the inside of the barrel.