I've just built a 20VT with a Wilson 10 Twist barrel and 20 grs. AA-2200 w/ 34 gr. HP (Varmint Nightmare) & 7½BR gives me 3800 fps with good accuracy and no Pressure signs. The Other Powder that is very good is Hodgdon CFE BLK - - 34 gr. hp w/ 19.0 grs. @ 3831 fps. with no pressure signs. I...
The 280 Rem. has the greatest amount of Bullet choices and some of the 7mm Bullets have the highest BC of any of the other calibers including the 6.5mm.