Powder Weight Vs Volume Measure Black Powder Vs. Pyrodex

[longcruise]

Here are a couple more experiments. Readers can decide for themselves what use they may be. :haha:

Comparison of powder by weight when measure is tapped and untapped before leveling the measure. The measure used is a Treso with the leveling type rotating funnel.

First, the 10 that were poured and sheared without tapping the measure

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

Weight volume Comparison of Scheutzen 3f to Pyrodex RS

100 grain volume setting throws 102.8 grains by weight of Schuetzen 3f
100 grain volume setting throws 73.6 grains of pyrodex RS.

This next one was done by a friend this might format screwy

Powder comparison for .50 Green Mtn Barrel, all loads 50 grains by volume Average
Swiss 3F 1524 1548 1545 1539
Goex 3F 1369 1373 1374 1372
Diamondback 3F 1362 1347 1338 1349
Goex 2 F 1304 1290 1313 1302
Schuetzen 3F 1257 1260 1280 1265

.40 caliber TC barrel, 40 grains

Swiss 3F 1847 1852 1838 1845
Average weight of 50 grains measured by volume
Swiss 3F 55.7 Goex 3F 47.9 Diamondback 3F 53
Goex 2F 52.9 Schuetzen 3F 51.5

In this last example, the fourth velocity is the average of the preceding three

 

[Billnpatti]

I have proven that the major concern is consistency in how you fill your powder measure. Some people will simply pour in the powder, scrape the powder measure level and pour the charge into their rifle. While others will tap the side of their measure to settle the powder in the measure. The fact is that as long as you do one way or the other consistently, it will make no difference.

I did an experiment in which I measured 80 grains (by volume) of 3f Goex powder and did not tap or settle the powder in the measure. I did that 10 times and weighed each filling on my Lyman LE300 scale. I had an average weight of powder of 76.63 grains with a standard deviation of only 0.3 grains.

I then repeated the experiment with the measure set again to 80 grains only this time I used my finger tips to tap the side of the measure until the powder was completely settled in the measure. I scraped the measure level and weighed each of 10 fillings. I found that my actual weight was 80.42 grains. The standard deviation was only 0.2 grains.

My conclusion was that either way, settled or un-settled, is equally accurate so long as you are consistant. However, if you tap the side of your measure one time and not the next time, you will have introduced a significant variation in your powder charge. The message is that accuracy lies in CONSISTANCY.

 

[Larry Pletcher]

I had a conversation with Bill Knight about how compaction or compression affect loads. He suggested an experiment to demonstrate this. He suggested filling a graduated cylinder to the 100 cc marker. Then tapping or vibrating the cylinder until the powder is finished settling. The results will vary with the brand and with the granulation size. An example he gave was 100 cc volume of ffg vibrated to 94 cc. Other brands of ffg will give different results. The point is that tapping of vibrating a measure will give different results with different powders.

BTW slug gun shooters and roundball bench shooters at Friendship use drop tubes. I have yet to see one who did not.

And last Bill's comment about consistency is KEY.


Regards,
Pletch

 

[coloradoclyde]

A valid argument can be made for using a drop tube when loading ......but not for the measuring of powder.

Your 100cc example increased the incremental variable by a factor of 20+

According to your example tapping a 80 grain measure of 2f would decrease the volume by almost 5 grains if I did the math right.

Even if that is true I still think consistency is the key and will be more noticeable on paper.

 

[crockett]

So....the drop tube goes in the bore to prevent grains from adhering to the bore. I wasn't sure on that.
I use to pour, rounded top, give one tap, then strike off the excess with a knife. Now I sort of a slow pour, no tap, and use the attached scraper to strike off the excess.

 

[Mad Irish Jack]

I use volume for all my ML rifle, smoothy and shotgun. Other than rb loads I use the old volume method for shot all my loads. I use my powder load and the shot load is 150% of the powder charge. 60gr pdr- 90gr shot /75 gr pdr- 112 or 113gr shot /80 gr pdr - 120gr shot and so on, works out great.