I have a 7mmBR rifle with a 26 inch barrel in 9 twist. Have been only shooting light weight bullets with very limited success. Spoke with an older fellow tonight at the range that use to shoot silhouette and he told me I'm selling the rifle short not shooting the heavies, like 150gr and up. He gave me about 150 of the Hornady 162gr A-max bullet to try. They measure out almost perfectly in my chamber, the recommended 2.400 COAL is a .042 jump in my chamber. My question is,.. can I use the Hornady load data for the 7mmBR in the book even though it's for a 15 inch barrel and just ignore the posted velocities? Hodgdon and Hornady don't have the same powders listed.