Thread: 7mm rem mag reloading issues

I would have to assume that a longer barrel would also allow an extra millisecond of time for a movement of some sort to affect bullet flight? Ie fundamentals and follow becoming even more important.. weird that the 1st 2 shots keep touching and then they chang poi consistently, across differing powder weights.. I would assume a shitty group not splits if it were 100% down to fundamentals and not be so repeatable. Could brass prep in way shape or form contribute?