The July 2004 issue of The Single Shot Exchange Magazine has an article by Jim Straight about Black Powders.
Some of the information and data don't apply to muzzleloaders because he used a Uberti Hi Wall in .40-65W caliber and was shooting 412 grain bullets, but some of it may be of interest to you.
In his tests he used 9 pounds of powder, 1056 primers and 62 pounds of lead. That makes my shoulder ache just thinking about it.
Because his interest is in BPCR shooting, he was looking for velocity and consistance for use on the 500 Meter Ram Targets.
He compared Elephant 2Fg, GOEX 2Fg, Schuetzen 2Fg, GOEX Cartridge 2Fg, Kik 2Fg and Swiss 1.5Fg.
From the data he presents, I am borrowing the numbers from his .050-.060 compression area as I think this represents about what a muzzleloaders powder would be compressed to.
This data gives the Grains of powder, but you should remember the weight represents the actual weight of the powder needed to equal a Volume required to give the .055 compression in his cartridges.
ELEPHANT 2Fg: 60.8 Gr, .060 comp. 1056-1079 FPS SD(Standard Deviation)7.14
Schuetzen 2Fg: 54.6 Gr, .050 comp, 1110-1138 FPS, SD 8.3
GOEX 2Fg: 54.25 Gr, .06 comp, 1105-1126 FPS, SD 6.4
GOEX 2Fg Ctg: 56 Gr, 1126-1148 FPS, SD 7.00
Kik 2Fg: 50.2 Gr, .050 comp, 1146-1170 FPS, SD 8.42
SWISS 1.5Fg: 52.5 .060 comp, 1207-1222 FPS, SD 4.12
The author also mentioned that Kik was dusty but seemed to give high velocity, and of course, Swiss was the hands down winner.
IMO the data is interesting, but because it was developed by shooting a .400 diameter 412 grain slug, it does not represent what the same powder would do pushing a light weight round ball.
I might also mention to those of you who don't get into number crunching, Standard Deviation is just a number which is a measure of repeatability or consistancy. The smaller the number is, the better the repeatability is.