I had a 280AI built last year. I have been tring to get 160 accubonds to shoot of of this rifle and they will not shot. I have tried different COAL 4 different powders two different primers. Just for giggles I tried 160 game kings and they shot great. The biggest group at just over a inch and he smallest at a half an inch. The best group I could get with the accubonds was two inches. Im just about to give up on the accubonds unless someone can give me some ideas.