mine went 3250 comfortably, could go over 3300 with extractor marks. 99gr of 872 powder, lilja 7T,M 30" barrel. didn't try other powders. i would not use a 3 groove barrel with this amount of overbore and Berger jackets. i have a friend that would dust 168 Bergers with a 9T and 6 grooves. i would recommend a 5R barrel as the minimum number of lands for this combo.