Actual Weights of Different Powders Measured by Volume

[PastorB]

I finally got around today to answering a question that I had been asked on another thread. That question was in regards to the actual weight of different powders when measured volumetrically. I set my volumetric measure to 70 grains, and here are the results. Each weight is a three "dump" average, but the max variance with any individual powder was 0.2 grains. I only used 70 grains, other weights can be figured by ratio if desired. All powders were 3F or sub equivalent, with the exception of Pyro RS.

Swiss 3f 63.7 grains

Goex 3f 58.8 grains

Pyro RS 48.6 grains

Pyro P 48.0 grains

Hodg. 777 53.1 grains

 

[necchi]

Cool.
What did ya learn? Honest?

I have just a few simple questions,
How does a "volume" measure differ from a "weight" measure when either is applied to the "actual load" found for the best accuracy of an individual and his rifle?
Is one of the measure methods more accurate than the other, or do the variables between each actually represent a rational comparison?

 

[Uncle Miltie]

It shows the difference in weight between GOEX and Swiss, and provides a likely reason for the performance difference between the 2 powders.

 

[PastorB]

Cool.
What did ya learn? Honest?

I have just a few simple questions,
How does a "volume" measure differ from a "weight" measure when either is applied to the "actual load" found for the best accuracy of an individual and his rifle?
Is one of the measure methods more accurate than the other, or do the variables between each actually represent a rational comparison?

Honestly, nothing worthwhile. I've been dumping 60 grains (volume, using a spout) of whatever powder into whatever caliber (.45-.58) with great results for so many years I just don't really care about small details. I was just asked that question about weights a while back. 60 grains, the Government service load in several muskets and rifles, just seems to be a sweet load for everything I do in all my guns. I use 3f, or equivalent sub, for everything but my original 170 year old 13 gauge SXS with a "London Fine Twist" barrel. Testing in many guns with many projectiles reveals a simple broad conclusion, Hodgdon 777 is the fastest fps, followed by Pyro P and Swiss which are exactly equivalent in every gun I have ever shot them in, and then Pyro RS and Goex 3f, which are also nearly equal, no matter the application, be it a pistol or a long gun.

 

[necchi]

It shows the difference in weight between GOEX and Swiss, and provides a likely reason for the performance difference between the 2 powders.

It does? Why an how?
What if someone with both powders uses 8% less of the Swiss by volume?
Or 8% more by weight of Goex?
Would the "performance" then be the same?

 

[Blackpowderart]

It does? Why an how?
What if someone with both powders uses 8% less of the Swiss by volume?
Or 8% more by weight of Goex?
Would the "performance" then be the same?

Doubt it....pound for pound swiss is hotter. Would be closer though...I just feel fancier when shooting swiss!

 

[jdw276]

It does? Why an how?
What if someone with both powders uses 8% less of the Swiss by volume?
Or 8% more by weight of Goex?
Would the "performance" then be the same?

Denisty. I am no scientist. I am retired. But with my homemade did a before and after pucking or compressing. I did 30 grain volume then weighted. Found over 25% increase in actual weight after pucking then and then screening for regular charcoal but only one grain increase with wilow charcoal. Willow is the charcoal to use I feel. More dense or actual weight equals more energy. Again I am no scientist, a retired accountant so I cannot explain the whys but I did try to make it an equal test to the best I could given my equipment. A more controlled test and better equipment might say more. But my conclusion the denser the powder the greater the energy. Thus swiss or willow charcoal equal more energy by volume.

 

[Uncle Miltie]

It does? Why an how?
What if someone with both powders uses 8% less of the Swiss by volume?
Or 8% more by weight of Goex?
Would the "performance" then be the same?

You are missing the point: same volume, different weight, different energetic properties between the two powders.

 

[LongWalker]

But the same weight of different powders will have different energy properties as well. Adjusting the actual weight of the charge (or as in Necchi's example, adjusting volume to arrive at the same weight) won't give the same results.

For simplicity, let's look at the adjustments needed to go from using the same lot of Goex FFFg to Goex FFFg. The chemistry should be the same. Density of a volumetrically-measured charge will differ, because FFFg will pack more tightly in the measure than FFg will. Due to the burning characteristics of the powder, adjusting the charge of FFg to get the same weight as the volumetrically-measured charge of FFFg won't give you the same results. Maybe the difference won't be enough to miss a deer at 50 yards, but it will probably show up on a 100 yard target shot from the bench.

Adjusting powder charges to arrive at the same velocity will usually give you the same point of impact (I'm not sure how to explain the cases where it doesn't, but suspect it has something to do with the way the gun recoils). You can also just adjust the powder charge to get the same point of impact as the original charge.

 

[user 49399]

Gallon of lead vs gallon of feathers. Same volume, different weight.

Pound of lead vs pound of feathers. Same weight, different volume.

 

[Grenadier1758]

Historically metals were measured on the apothecaries' scale of 12 ounces to the pound. Feathers were measured on the avoidupois scale of 16 ounces to the pound. A pound of feathers was heavier than a pound of lead.

Now, of course, no one uses the apothecaries' scale so both lead and feathers weigh 16 ounces to the pound.

 

[longcruise]

More dense or actual weight equals more energy

I've done extensive similar tests and also compared the velocity of the same powders using the equal volume of powder. The powder with the greatest mass (weight) for those identical charges delivered the lowest velocity (Elephant). Actually quite a bit lower! As you can see above, Pyrodex is much lighter with identical volume but it shot velocity right alongside goex and graf.

 

[Loyalist Dave]

But my conclusion the denser the powder the greater the energy. Thus swiss or willow charcoal equal more energy by volume.

Well no you found a correlation with the weight vs the results that you measured..., which works fine so long as the ratio of combustible materials does not change. Meaning, I could have an even denser lot of BP and thus it weighs more than yours, BUT if the weight was from some manufacturing mistake, and the added weight was from non-combustible ingredients... I'd actually get less power than you. Further, the size of the granulation is another factor. Smaller granulation = more surface area = faster burn time = higher pressure = more velocity (power). So If a BP manufacturer followed your procedure BUT made cannon grade powder at the end (larger granules than 1F) then lower power would be the result, as the burn time would be drastically less than yours.

LD

 

[DixieTexian]

Interesting that Swiss is 8% less dense. Since it is sold by the pound, you then get 8% fewer shots per pound using the same measure. However, if you back off on your load when using Swiss, as many do, that 8% probably evens out, which means it's higher price doesn't even out in the end from backing off your load versus Goex.

 

[Jim in Wisconsin]

It seems wrong to me to say "xx grains, measured by volume". Grains are a unit of weight, there are plenty of ways to express volume, like cubic inches, cubic centimeters, gallons, etc. Why do it wrong when it's so easy to do it right?

 

[64Springer]

It seems wrong to me to say "xx grains, measured by volume". Grains are a unit of weight, there are plenty of ways to express volume, like cubic inches, cubic centimeters, gallons, etc. Why do it wrong when it's so easy to do it right?

So what do you suggest?

Powder measures with no numbers of any kind on them.

Folks just hazard a guess at how much powder is in their measure?

40, 45, 50, 55, 60, 65, 70 grains and so on imprinted on a measure is just a guide.

Something repeatable and consistent.

 

[Jim in Wisconsin]

I suppose I would suggest using volume units, like cubic inches or cubic centimeters.

 

[Okie Hog]

Use a different measure and get different results? What measure did you use?

777 is named that because 100 measured grains weight 77.7 grains.

 

[64Springer]

Use a different measure and get different results? What measure did you use?

777 is named that because 100 measured grains weight 77.7 grains.

Learn something new every day.

 

[64Springer]

I suppose I would suggest using volume units, like cubic inches or cubic centimeters.

That's fine for a 327 small block.

But how would you apply it to muzzleloading?