Some potential powders, but no guarantees concerning muzzle flash. And then, there is the question of availability.
Cartridge : 6.5 mm Rem. Mag.
Bullet : .264, 125, Nosler PART SP 16320
Useable Case Capaci: 60.597 grain H2O = 3.935 cm³
Cartridge O.A.L. L6: 2.806 inch =...