I believe you have to add 4-5gr of 4198 to put both bullets 560gr in one point. I got the same with 520gr bullets. First try - about 20" apart at 50 meters. Added 5gr - 8" apart. More 5gr - Bingo!
But I use Finnish VV powder #120, which is allmost the same burning rate as 4198.


Geno.