bearing length vs accuracy

[tomestone]

For powder and primer? H-1000 and a FED GM 215 M

I just got back from the city no RL17 or H1000 or Berger any thing,so But I pickup 100 rounds of Nosler Accubonds 200gr. and do have IMR 4350 .Iam intrigued with what I learned here.ThanksAny suggestions.