Looking for a starting point on my 280 AI. I am wanting to try some of Bergers 180 VLD's and I need to know where to start. I want to try H 4350, H 4831, H 1000, VV N 160, VV N 560 and maybe some R 22. Out of these powders I have listed, what would you start with? I have them all so it doesn't matter where I start. I am looking for a powder that will hopefully not be real temperature sensative and that will push the 180 Berger to 600 yards accurately. I am doing some competition shooting at this yardage and it will not be a hunting load that I'm looking for. I am shooting a 24 inch barrel with a 10 twist barrel, Nosler brass (3 firings) and CCI BR2 primers. I know that Berger suggests a 9 twist barrel for the 180's so do you all think I am waisting my time with the 180's and should I drop back to the 168's with the 10 twist barrel for bullet stability? Let me know what you think, maybe you all can save me some time and components. If you think I need to go with the 168's say so. Thanks, BK.