You know I once bought what was supposed to be 1 lot of 125 rnds turns out after much cussing and frustation that there were infact 3 differant case capacities . The result on paper however at 1st looked like 12" groups,shooting upto 10 at a setting . I finally after the 5th or6th setting desided to just empty all the brass and start from scratch,at about 50 rnds I found not a 12" group but 3 very separate 3" groups. This same rifle when hand loaded will put 5 in a 4 cut hole add .3 grns it opens to 1.5 add another .3 and its out to 3". Some rifles are just picky .

My standing advice shoot the load that yields the best groups even if its the bottom shelf white box after all those old school cup and core bullets probably only killed a couple of million deer ,elk and moose before Mr.Nosler or Mr Barns were born.