According to the Lyman BP Handbook, the .58 round ball has a higher B.C. than the .54. ( .535 = .075; .570 = .080) As a matter of fact, as the diameter of a round ball increases, so does the ballistic coefficient of the ball, becausethe coefficient of form for a round ball is the same regardless of diameter, and a ball's weight increasesina greater-than-linear progression. What this means is that, if launched at the exact, same velocity, a larger, heavier ball will ballistically outperform a smaller one every time!

Because of this, for a .54 to exhibitbetter down range velocity levels, energy levels, and less drop than a .58, it has to be launched faster than the .58. However, that is relatively easy to accomplish. For example, the "standard" charge for the Hawken plains rifle was generally stated to be "one-half the weight of the ball". So in a .54 with a 230-grain ball, this is 115 grains. Not at all out of line. I personally use 110 in my .54 Hawken. But for a .58, in which the ballweighs over 270 grains, this charge would have to be 135 to 140 grains, which is quite an increase just to get to the same velocity the 115-grain load gives in the .54.

Basically, the .54is generallyloaded to give a higher MV than is the .58.Consequently, its' downrange performance is more impressive.

Additionally, there's a BIG differencein recoil! Given an 8.5 pound rifle, a .54 with a 230-grain ball and 115 grains of powder gives 32 Foot/Pounds of recoil at 1700 FPS MV. A .58 of the same weight firing a 270-grain ball at the same MV, using 140 grains of powder, has 48 Ft/Lb of recoil-an increase of 50% over the .54!!