Don't know if I should go ahead with this what with so many showing such sarcasm toward science!
Oh well, here goes. This is going to be kinda long.
Comparison of powder by weight when measure is tapped and untapped before leveling the measure. If memory serves, this was done with scheutzen 3f.
First, the 10 that were poured and sheared without tapping the measure. This was done with a measure with a shear top funnel.
93.5
94.1
93.2
92.5
92.8
93.6
94.0
92.8
93.5
92.2
93.2 Average Weight
.63 Standard Deviation
1.9 Extreme Spread
Next, the ten that were tapped and then sheared
94.3
94.2
93.5
93.9
93.8
94.1
94.1
94.0
94.1
94.3
94.0 Average Weight
.25 Standard Deviation
.8 Extreme Spread
So, tapping is more consistent. I'm not impressed by the difference and have not taken up tapping!
Next, I set a benchtop powder measure at an arbitrary setting and dropped and weighed charges with a balance beam scale.
Graf 3f
55.9
55.5
55.5
55.3
-------
55.55
Goex 2f
51.1
51.7
51.3
51.4
-------
51.37
Goex 3f
52.2
52.1
52.5
52.2
--------
52.25
Elephant 2f
60.2
60.4
60.4
60.1
---------
60.27
Swiss 1.5f
55.9
56.1
56.4
56.2
------
56.15
Swiss 2f
57.4
57.2
57.2
57.4
-------
57.30
Pyrodex RS
37.0
37.1
37.5
36.8
-------
37.10
So, as you can see, volumes and weights vary widely from maker and granulation. Take what you want from this. For me it advised that you pick a powder and shoot it. That simple. Weight or volume, just be consistent. I wish I would have had some various lot numbers of the same brand and granulation to look for differences in lots.
This next data set tells us a bit more about the actual performance of these powders. Pay attention to the mass (weight) of the various powders based on the previous set of data and the velocities produced (energy output)
Average velocities for various powders with charges thrown from 50 grain volumetric measure. and shooting a .530 patched ball from a 32" .54 caliber barrel
Graf 3f
1405
1388
1370
1391
1396
Avg 1390
Elephant 2f
1135
1208
1215
1215
1238
Avg 1201
Swiss 2f
1546
1531
1574
1558
Avg 1552
Goex 2f
1349
1362
1376
Avg 1362
Goex 3f
1469
1516
Avg 1492
These two velocities were the only ones obtainable due to bright sun and erratic chrono behavior
Pyrodex RS
1494
Only one good reading due to changing light conditions on the chrono.
No surprises here. Swiss as expected is the most energetic. Notice however the clear loser on energy was the powder in the volume weight comparisons that threw the most weight by volume. I don't think Elephant is available anymore. The Brazilian factory had a safety record that made goex seem like a good place for a daycare center.
In the market today, the best buy in powder including subs is clearly pyrodex. it's less expensive than any of the holy black and Just as Hodgdon has always said, "more shots per pound" and performance right along with Goex.
That said, I use Scheutzen and have for a few years now. As good as pyrodex is performance wise my own experience says that it can be a bit picky in ignition. In a cap gun, little anomalies or fouling in the flash channel that are ignored by the black become a hangfire with Pyrodex.
As good as Swiss is, I get good velocities and accuracy with Scheutzen (and always have with Goex). The additional cost is enough to dissuade me from buying Swiss.
@Jitterbug This is why I don't consider the use of scales vs volume to be a safety factor. Even though there are differences between wgt and vol, there is not enough to make a difference in terms of safety. One might say that there is considerable difference with Pyrodex, but it's hard to actually buy Pyrodex without being informed of that and in addition, I don't believe there is enough difference to warrant concern.
When a rifle or barrel manufacturer says "max charge xx" it's obvious that there is wiggle room.
Once I did these tests I never again paid any attention to the popular ballistic tables in various manuals and books. They obviously are meaningless IF you want truly accurate information about your ball/patch/lube/powder/rifle/barrel length, etc.
The other thing that I no longer pay much attention to are the endless conversations about how much powder to take a (insert animal of choice). Clearly there is more to it than the volume or weight of the charge employed.
And, finally (whew is he finally done!
) to me these numbers only say that there are or can be significant differences in powders but they are not etched in stone. Who knows what the differences may be between the powder tested today and these tested back then. Batches and lot numbers can vary. Just measure it your own way and shoot it.