Well today I thought I would try a couple of different 6.5Creedmoor ammos,I usually shoot 140GR so today I tried 129 Winchester and it was all over the place at 200 yards. I thought maybe some different impact zone but with 20 shots it looked like a shotgun patern.So i went back to 140gr and i was back to 1in groups.but the guy shooting next to me uses 129 and he is right on tight groups.