Agree wit Btroj. I have for years used 22 gr. of 2400 with one grain of fluffed Dacron over powder in my #1 45-70. Killed a lot of paper with that load, and one real good sized boar in Tex. with that load. Think It chronos about 1250 or thereabouts. Have nothing against Unique or 4064, and am sure both will do the job. Being cheap, would not use 4064 just because of vol required to launch at the same vol as Unique. Would use Unique because of the obvious more bang for the buck. I shot a lot of Unique in mine, but 2400 had an edge over it, so have stayed with 2400. If I were to need more umph, would go up with 2400 to probably around the 26 gr. level or more, as the 22 gr. I am shooting is nowhere near the top load for my rifle.
1Shirt!