I was wondering, if a change of my "technique" would result in a different mean charge weight.
Technique 1 "The Trickle":
Let the powder flow into the dipper and level off.
Technique 2 "The scoop":
Scoop to th bottom, turn up, raise and level off.
The test:
mass thrown [g]
1 2,95
1 2,91
1 2,95
1 2,94
1 2,93
1 2,93
1 2,96
1 2,99
1 2,93
1 2,97
1 2,9
1 2,91
1 2,94
n= 13
SD= 0,025
Mean= 2,939
Min= 2,9
Max= 2,99
2 3,01
2 3,01
2 2,93
2 2,98
2 2,91
2 2,93
2 2,94
2 2,9
2 2,99
2 2,99
2 3,02
2 2,99
2 2,97
n= 13
SD= 0,041
Mean= 2,967
Min= 2,9
Max= 3,02
So the method 2 of scooping gives a high mean charge mass than method 1 The Trickle.
But is this likely to be by chance or not?
Ttest tried:
p of F-Max--> 0,121262235
Use Equal Variance
Equal Unequal
Variance Variance
Mean diff. -0,027692308 -0,027692308
SE 0,013197035 0,013197035
t-value -2,09837342 -2,09837342
df 24 12
two-tailed p 0,046577672 0,048645165
The result for two tailed p being smaller than 0,05 indicates that the differences detected are most likely (95%) not by chance alone.
Lessons learned -
Lee dipping with the powder used gives 0,05 g +- / ~0,8 gr. +- extreme spread for target charge mass.
The way of dipping has an influence, do not change - as per their instructions.
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Disclaimer:
This little test assumes no validiy for any other components or results by other "dippers".
I am hamfisted and all you numismatics probably get the charge mass right just by feel...
