I thought I would show a test using a Cable's 54 caliber Hawken caplock rifle. Each powder increment had a standard deviation of 10 ft/sec or less. In this test, I had one powder increment at 7 ft/sec. This rifle had a maximum charge of 100 grV.
60 grV - 55.5 grW - 1224 ft/sec
70 grV - 65.1 grW - 1322 ft/sec
80 grV - 74.6 grW - 1394 ft/sec
90 grV - 84.4 grW - 1467 ft/sec
100 grV - 93.3 grW - 1540 ft/sec
Velocity change from one powder increment to another
60 grV to 70 grV - 98 ft/sec
70 grV to 80 grV - 72 ft/sec
80 grV to 90 grV - 73 ft/sec
90 grV to 100 grV - 73 ft/sec
You can see the change between powder increments. The shooter can make a choice on what to use. The more powder used the higher the cost and recoil. This test shows the powder efficiency. The shooter may want to check the grouping from one powder increment to another. I have had club members shoot through my chronograph with their muzzleloaders. The shooters were surprised with standard deviations of 50, 60, and sometime 70 ft/sec. It is the little things in the loading procedure that drives up the standard deviation. If the shooter has wide changes in velocity, the trajectory will be effected. I have noticed considerable change between rifles. Sometimes shorter barrels will have higher velocities than longer ones. Even rifle by the same manufacture and caliber will vary considerably. It is what ever the shooter wants. I just have fun taking a gun testing the powder increments. I have learned a lot from my chronograph.
Good shooting
