Powder Measures - Only a novice would ask

D

Doc Hoy

New member
Experts,

I am not completely new to BP shooting but I just never thought about this before. Maybe I have too much time on my hands.

I bought a CVA - 1400 powder flask with a 30 grain spout. I assumed this flask would give me a fairly accurately measured 30 grains of powder.

In the way of verification, the way I use this flask is to turn it with the spout down. I cover the end of the spout with my finger. I open the gate to allow powder to trickle into the spout. I shake the flask lightly to make sure the spout is full of powder. With my finger still covering the end of the spout, I allow the gate to close, turn the flask upright and then remove my finger. The spout is now filled to the rim with powder.

Well unless I am sadly mistaken, "grains" is a measure of weight and not volume. So the powder flask and every other powder measure I have used meters out an appropriate volume of powder which is supposed to correspond to a given weight. In the case of my CVA flask it is supposed to be 30 grains.

The problem is this. When I weigh the charge of powder thrown by this flask, I get 19 to 20 grains every time. Doesn't matter if the flask is filled with Goex fffg or Pyrodex P. I am using a scale which I think is relatively accurate. (Manufacturer says it is accurate to .5 percent through its entire range. I have been using it to weigh bullets and it is giving me weights that are appropriate to caliber using pure lead.)

So I thought, "Maybe The CVA spout is not a 30 grain spout." I tried the flask with two different powder measures I have been using (telescopic jobs.) and the CVA flask throws a fairly consistent 28 grains of powder as measured by these other two volumetric telescopic powder measures.

I have essentially two questions.

1. What is wrong with my thinking?

2. Should I stop thinking about powder measured by weight and just think of it as measured by volume?

Please help, because I feel like I can't go shooting until I get this issue resolved.
 
Doc it's a volumetric measurement that 30gr spout you have with a lite finger pressed on it would be 28gr by volume. No need to weigh it.
The volume is to be per grain = to the wieght of Black powder by the grain only. That's why the standard volume measurement is used, as pyrodex and other subs are lighter by weight, but measured as = to by volume.
30gr +/- .5(error margin of scale) = 30.5/29.5 (finger indent 2-4gr).
As long as all chambers are measured by volume the same way it don't really matter as long as they are accurate and consistant.
 
From about.com

Some folks wonder why black powder is not metered the same way that smokeless powder is. To further confuse the issue, both measurements are quantified using the same unit of measurement (grains), even though the measurement processes are quite different. Here is some information which may help clear up the confusion about measuring different kinds of powder.

Both black powder and smokeless powder are measured in grains - but black powder is measured by volume, and smokeless is measured by weight.

The reason is that black powder is a simple chemical compound (made of sulphur, charcoal, and saltpeter) of a given grain size (Fg, FFg, FFFg, etc), and can be relied upon to produce consistent loads when measured by volume. A volumetric measure (one small scoop, for instance) of FFg black powder can be expected to contain the same amount of powder - therefore the same explosive potential - time and time again.
 
Okay...Now I can go shooting again

Thanks fellas,

Halle--friggin---lujah...I just found the documentation.

I just drug out my Lyman Muzzleloaders Handbook (1976) and found, on page 92, a comparison by weight of Pyrodex to black powder. Sure enough, Pyrodex weighs about 80% of what black powder weighs.

Now I can go shooting again....

I do have too much time on my hands!
 
This is almost as messy as cap size.

First, the important thing isn't whether your measure throws exactly XX grains. As Smokin' Gun implies, the important thing is that it throws the same amount each time you set it for XX grains.

There are a couple of reasons your flask spout throws something other than 30 grains of powder by weight. One is that the powder in the spout isn't sifted to it's minimum volume. Yes, you shook it a bit, but you'd really have to vibrate it to make that happen. Second, the volume/weight ratio was originally based on water, not black powder, and although it's close, the graphite coated black powder we use today has a slightly different volume weight ratio.

Now for the messy part. Guess what: the volume 'calibrated' measures we use don't measure the same amounts. A friend on another forum posted some interesting data the other day: He had two adjustable volume measures with different inside diameters, one 0.350", the other 0.430 inches. He set both at 20 grains and measured the depth in each. The smaller one measured 0.805" deep, the other measured 0.570" deep. He did the same thing at 30 grains and got 1.125" and 0.845". The difference in volumes at the 20 grain setting is 0.02134 cubic inches; at the 30 grain setting it's 0.05789 cubic inches. That's an error of 7 percent at 20 grains and 13 percent at 30 grains.

What he didn't do was actually measure some charges and weigh them, and I suspect if he had he'd have gotten a bit less error due to the 'compaction' issue, but the bottom line is your 30 grains, by volume or weight, is probably not my 30 grains, and neither of us will have the same amount of powder as Smokin' Gun's 30 grains.

And, as I said above, it doesn't really matter as long as we each use the same measure at the same setting each time.
 
First, the important thing isn't whether your measure throws exactly XX grains. As Smokin' Gun implies, the important thing is that it throws the same amount each time you set it for XX grains.
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Hunh Mykeal, I implide what now?
30gr +/- .5(error margin of scale) = 30.5/29.5 (finger indent 2-4gr).(this is called a discriptive example) :O)
As long as all chambers are measured by volume the same way it don't really matter as long as they are accurate and consistant.
 
This is getting interesting

Mykeal,

You talked about your friend measuring diameter and depth, but in the case of both of my telescopic measures, the bottom of the measure is not flat but dome shaped, I assume to aid in completely emptying the measure. So on mine, the measure of depth may be close but will not be exact. Seems like a purist would be better off making his own measure. On the other hand, I am convinced that the CVA flask throws a fairly consistent charge. It certainly did when I was playing around with the scale. All measurements were within 5% (assuming that any error in the scale is consistent across measurements, which it probably is.) over about two dozen tests. This is true even considering that I am not able to judge the amount of pressure I am using with my finger. The indentation of the powder was always roughly the same and I think at this point that I may be splitting hairs.

This "dome versus flat bottom problem" (along with some others) goes away with the purchase of the CVA flask. Smokin Gun was right about the pressing-the-finger-into-the-spout-thereby-reducing-the-volume-of-the-charge syndrome. I did not mention that in my first post but it is clearly the reason why I get 28 grains instead of 30. I can live with that. (Heck, I can live with dang near anything!)

As is always the case, posting and reading this forum has been a real education
 
Seems like a purist would be better off making his own measure.
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Actually, all of the 'purists' that I know personally do just that - they're made of antler, bone or wood and are not adjustable. They're usually carried on a leather thong attached to the powderhorn sling. Some don't know how much the measure throws; all they know is their rifle is accurate at a given range with that load. And it brings down the game.
On the other hand, I am convinced that the CVA flask throws a fairly consistent charge.
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I don't believe I said otherwise.
 
A powder like this one from DGW is really good for revolver owners that want to shoot several charge sizes. I over fill mine slightly and when you swing the funnel back in position it wipes the excess off. The funnel makes it easy to fill cylinders down to .31.
 
I like this one from Thompson Center. They don't make them in solid brass anymore but they're still good measures. This one is over 20 years old. I have two of them. One for rifles and one for pistols.

100_0844.jpg
 
Hawg I think those T/C Measurers are cool as hell ... I have had mine tire gauge one for about the same time. Was the rifle one with a funnel, I was only shootin' mostly long guns the time.
Don't use the funnel but it's in my bag.
Recently got a swivel funnel measurer like was pictured only in 0-120 for the Revs.
But I like yours the best ...
 
Yup!

To Hawg and MCB,

The one I was using is precisely the same as the photo in Hawg's post. I've been using it for about a year now and compared to empties with brass rods soldered onto them, it is the best thing since sliced bread.

Only thing that gives me a hard time is filling it up.

There is probably a better way that I don't know about, but I was filling the measure from the powder bottle. I got hold of one of those tapered plastic spouts that screws onto the plastic bottle in place of the cap. No matter how much care I took filling the measure I always wound up losing a little powder either because the wind blew it away, or the measure got just a bit too full.

I never lost much, probably never more than a shot's worth of powder in a day of shooting. Its the principle of the thing. At 25 bucks a pound I am pretty careful with the powder. Not only that but who knows were that powder is going? Can you imagine a racoon coming around after I gone, sniffing up all that powder? Poor thing wouldn't be able to taste anything for a week. I knew a gunner's mate when I was stationed on the U.S.S. Peterson who used to put gun powder on his hamburgers. He said it was to enhance the tools of his manhood. We told him it was just so he could shoot off his mouth. Anyway...

I know this CVA flask will do what I want it to do. Now that I am better educated on the difference in weights of substitute powders compared to BP (for which I have all of you to thank) I will have less concerned about the accuracy of the charge I am putting into the pistol.
 
I use a horn tip, with a nail ran thru it at 50grs.

You can never use to little, or to much.

Ive been shooting flinters for 30 odd years now.

Find the best load for your rifle, then make a fixed measure.

Ive never had a rifle that didnt shoot well with the same gains as the caliber +/- 10 grains.

Here is my shooting pouch

You can see the nail inside the horn tip, when the powder hits it, I hit the target.

Note also my Rev War British warrant pan charger ( not many around these days.) An brass snuffbox to keep my patches moist and seperated in the hot summer, or dead winter cold.

pouch.jpg
 
I fill my measure from the flask. I don't load directly from the flask because it only takes one hot ember to turn a flask into a grenade.
 
Good Point

H.H.,

Good point.

It doesn't work to say, "Well that never happened to me before." Because it is the kind of thing that only has to happen once.
 
It doesn't work to say, "Well that never happened to me before." Because it is the kind of thing that only has to happen once.
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This is precisely why I've taken to making cigarette paper cartridges for my revolvers and carrying them in brass and aluminum tins.

I use the same measure madcratebuilder mentions above to measure from a flask, to my formed rice paper tubes. A twist to each end, some sticky stuff to keep them closed and bingo, single use BP charges!

Makes for a few enjoyable evenings each week, twisting them up, and exercising my aging thumbs and eyeballs. Still can get over going into a store at my age though, and asking for "rice paper cigarette papers, please."
 
That's a nice measure Hawg, I'll keep an eye out for a used one.
My one and only experience at making paper cartridges was OK, but seemed awful time consuming. I have read and seen more ideas on the forums about it. I well give it another go.

I usually load up three or four guns and blast away, then set and reload, get my heart rate back down:eek:
 
Measure

MCB and Hawg,

The one I have looks exactly like Hawg's. But I think it may be slightly different in the powder graduations. It starts at 20 and goes up to (I think) 90. If the lowest number on Hawg's is twenty, it is the same measure.

I got it in a parcel of stuff that came with a pistol that I bought at a gun show a while back. In fact, now that I remember, one of the things was a nearly full container of Pyrodex that was marked $10.99. That'll give you an idea of the vintage. The Pyrodex is fine. I shot some of it up the other day.

BTW MCB, The loading part is what gets my heart rate UP. :)
 
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