I was out today with my new GPR flintlock in 50 cal. I put a 57 GPR peep sight on it and away I went. I never adjusted the sights at all. Load was 90 gr Goex 2f, .490 speer ball, .018 TC Pillow Tick pre-lubed patch. I was shooting off a sandbag on a table. At 15 yds I was nice and tight, then I moved it out to 50 yds and things started to spread out a bit (lot). I think part of my problem is inconsistent sight picture. I've spoiled myself over the years by using scopes, so now I have to re-learn how to shoot all over again.
http://img.photobucket.com/albums/v445/HuntAway/Lyman%20GPR%20Targets/GPR90GrGoex2F.jpg