Im trying to work up a 6x44mm , Lapua brass, H4350, N160 and Berger 105 hybrids. Goups are 2 shooters, but what worries me is the more I shoot(only about 30 rounds) the worse the copper fouling gets. Patches sail right thru smoothly, but they are blue _BLUE. cleaned after each shot for 3 then after every third shot. JB(thinking about J&B at this point) cleans it up, but it comes right back. This is a cut rifled barrel of a respectable maker, smithed by a very respectable firm. Any ideas or do I just have a barrel with bad genes?