I am going to put together a 26 inch barreled 264 Winchester magnum using a 1 in 12 twist Lilja barrel and would like some good info on usable bullet weights. I am hoping to get at least 3400 fps with the 120 grain speer bullet. The rifle will be used for Wyoming antelope and mulies with generally shots taken at mostly brodside animals. What would be the best powder for top velocities? Lotsa questions for my first post on this board but it seems to be just what I am looking for.