Pyrodex weight, powder measures?

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ArmedBear

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I've got a few things around the garage.

Thing #1: collection of unmarked powder flask spouts my Dad dropped off one day. I used them 25 years ago, and I'm using them again. But now I want to mark them, because I can't remember worth a #$%! what size each one is!

Thing #2: Pyrodex in three forms: 30 grain-equivalent revolver pellets, P and RS powders.

Thing #3: RCBS powder scale

Thing #4: T/C adjustable volumetric brass black powder rifle measure

So... I know Pyrodex isn't BP, but I'd rather not BUY BP just for the sake of measuring spouts.

Anyone know whether:

A. Pyrodex weighs anywhere near the same as BP?

B. 30 Grain Pyrodex pellets weigh the same as 30 grain BP equivalent by volume, of Pyrodex P powder, so I can use the pellets as a reference?

Or... Any other thoughts about how to figure out the charge that each spout measures?
 
Pyrodex is measured by volume. Use your volumetric powder measure to check the spouts. 30 grains BP on the measure will throw 30 grains equivelent of Pyrodex.
 
Formerly, Hodgdon stated that if one was absolutely desperate to weigh charges, one could weigh Pyrodex. However, it was a complicated, convoluted procedure and had to be redone every time one changed producton lots of Pyrodex. Better to simply use volume measurement.

Use your regular BP volume measure and the same volume of Pyrodex will be just fine. Remember, that a large portion of these propellants remain unburned and are pushed out the barrel, so excessive attention to detail is unwarranted.
 
Oh yeah, I've spaced out and double-charged a .50 rifle, and all that happened was more recoil and a lot of burning powder spewing from the muzzle.:D

The T/C measure is marked in 10 grain increments, but I suppose I can pour a reference measurement of an even 100 grain-equivalents by volume and base my calculations on that.

I didn't know the stuff varied in weight so much from lot to lot. I just thought it was measured by volume because it didn't weigh exactly the same as BP. I never had a powder scale until I started reloading smokeless, so I never weighed Pyrodex before.

I suppose I could just use Cream of Wheat, too, if I do a weight/volume reference measurement off my rifle powder measure. But where's the excitement in using something non-flammable?:)

Thanks!
 
Or... you could just buy a pound of real black powder. Weigh the charge each spout throws of the real black, mark them with that number and you would be good to go with the substitutes.

Steve
 
>you could just buy a pound of real black powder. Weigh the charge each spout throws of the real black, mark them with that number and you would be good to go with the substitutes. <

Nope, sorry.

Black Powder is measured by volume grains, sometimes called water grains. It is sort of like using a bulk specific gravity (which is akin to a bulk density). What one does is to measure the volume occupied by, say, 60 grains of water and then use that volume measure to measure out the 60 grain charge of powder.

Measuring substitute powders by weight will lead to incorrect charges.
 
Wait, Bad Flynch...

If THAT is true, can't I just fill the powder measures with water and weigh the water?

That seems like it might be more accurate, if I do it right.:)
 
why complicate this?

Just drop a charge in the spout, drop it into the measure and bring the measure up to see what the volume charge is - you may want to do this 3 times and use the average number.

That's all the more complicated this needs to be and will give you a correct number.
 
Just drop a charge in the spout, drop it into the measure and bring the measure up to see what the volume charge is - you may want to do this 3 times and use the average number.
Click to expand...

I did this. It didn't work well.

The measure is made for a .45-.54 caliber rifle. It's graduated in 10 grain increments.

The spouts for powder flasks are something like 18, 21, 24, 27, 30, etc.

I think I'd be better off weighing 100 grains by volume from the measure, then weighing whatever the flask throws. This should bring the error down to the point that I'm getting meaningful results.
 
Well, I haven't ever heard of volume grains. A grain is 1/437.5 of an ounce. A grain of powder, a grain of water, a grain of lead or a grain of feathers all weigh the same.

My spouts have been marked based on the weight, in grains, that they throw using black powder. The volume within the spout is constant. The weight of the contents of a spout vary depending upon what you fill that volume with. Since the substitutes are a volume for volume substitute of black powder, I have been perculating along quite nicely using that method.

Steve
 
I understand what grains are. I reload with smokeless powder, too.

The point is that I have a collection of unmarked spouts that I put in a box over 20 years ago, and recently got back from my Dad. I used to know what they were, but I have no idea any more. I need to measure what they throw to mark them.:)

However, the only accurate way it seems I can do this is to weigh a reference amount of some powder (Cream of Wheat, Pyrodex, whatever, measured by volume, in a known powder measure, preferably much larger to reduce error), weigh what each one throws, then calculate what this volume is WRT the known volumetric equivalent of 100 grains BP.

It isn't like weighing smokeless powder, it seems. And I knew that, because Pyrodex is made to be measured by volume. But I didn't know HOW screwy the measurement of BP in "grains" really is. It seems it's not grains of BP at all, but the volume of BP that equals the volume of water that weighs X grains. Trippy stuff.

Still, I know what to do now.

Thanks all!
 
OIC

Didn't understand that the measure was limited in that way. Maybe just getcha a fully adjustable "plunger" type measure - good to have anyway... not too much money. The one I have goes to 120 grains and is infinetly adjustable and graduated in 5 grain incremements but you can guess close enough between the graduations - I guess you can't with your current measure.

OK - I just went out and took a look at my set of spouts - perhaps they are the same size as yours - they are graduated as follows: 18, 21, 24, 30 and 45. That last one was unmarked or the stamp didn't take - it seems to measure out 45 grains though.

Hope that helps some.
 
I have a big T/C plunger measure. That's where I'd get my reference amount. Maybe it does go by "5 grain" increments (using quotes because I now know it's not really 5 grains of powder).

Either way, I found it hard to use it accurately enough to tell the difference between 18, 21, 24, 27, 30 or whatever I have in my old collection of flask spouts. I could tell pretty well using the plunger if they were, say, 20, 40, and 60, but not when the increments are a few grains.:)

For a revolver, I like to just use the flask with a fixed spout. Simple, quick, nothing to screw up, and the chambers come out even with each other. But it's good to know how big the spout is.
 
>A grain of powder, a grain of water, a grain of lead or a grain of feathers all weigh the same.<

True, a grain of lead and a grain of feathers weigh the same, but their volume is different; they have a different specific gravity.

If you have a spout of unknown delivery quantity, then take the spout out of the flask, tape off the bottom, and weigh it. Then weigh it level full of water. The difference between the two weights is the weight of the water contained in the spout --and-- the number of water/volume grains of powder. But, you still must use the spout to measure whatever powder you are using to get the correct amount. Weighing it just will not do, especially when it comes to the measurement of Pyrodex and some others. Black seems to work well regardless.
 
Bad Flinch

Think I'm finally beginning to comprehend volume grains.
Please correct me if I'm wrong.

They used water/volume grains because water always weighs the same, unlike blackpowder which differs in weight.
Therefore, if you take 60 volume grains (actually the volume of 60 grains of water) you can always have the same volume of blackpowder, regardless of the blackpowder (or BP substitute's) weight grains.

So if someone says 'use 60 volume grains' he means 'use the identical volume of BP that 60 grains of water has'
Right?
 
Sounds like an approximation of the metric system, before they invented the metric system.:)
 
The conversion chart shows that Pyrodex RS weighs 68.4% of the equivalent amount of ffg black powder. That means that if you have a given weight of Pyrodex RS and you want to know what weight it is equivalent to in black powder, you multiply the amount of the weight of Pyrodex by 31.6% (or .316) and then add the two amounts together (The original full spout weight of Pyrodex + the 31.6% more amount).
OR, you could just multiply the full spout weight by 1.316 to find the BP equivalent volume/weight.

Simply put, BP ffg weighs 31.6% more than Pyrodex RS.
So fill your spout with Pyrodex and weigh it, then multiply that amount by 1.316 and you can determine the approximate equivalent weight (which theoretically equals volume) of it to BP.

If you're checking the spout volume by using Pyrodex P, then you would add a grain or 3 (5-10%) to your final equivalent BP weight (which equals volume) calculation.
The weight of BP is reportedly very close to the calibrated volume measurements of most powder measures. I've seen reports of people that have weighed many charges from their measures to test for volume consistency, and the weights are usually very close to the volume, unless the measure is poorly made. Since you are not testing a volume measure, that's not really an important issue to consider here. You are testing the volume of the spout by Pyrodex weight, and then simply converting it to the approximate BP weight.
 
Last edited:
Hildo wrote: They used water/volume grains because water always weighs the same, unlike blackpowder which differs in weight.
Therefore, if you take 60 volume grains (actually the volume of 60 grains of water) you can always have the same volume of blackpowder, regardless of the blackpowder (or BP substitute's) weight grains.

So if someone says 'use 60 volume grains' he means 'use the identical volume of BP that 60 grains of water has'
Right?

That is pretty near it. Water at the same temperature always weighs the same per unit volume, and the rest is just fine. Specific gravity and density measurements are typically done at STP (20° C = 68° F), although exceptions exist.

I will surmise that this is more of a practical thing: can you imagine carrying a musket or flinter into battle and having to weigh powder in the heat of battle? Not me! Measuring by volume is a very practical solution to a major problem and the accuracy is sufficiant for the job.
 
Since I have been totally unaware of the proper way to weigh black powder, just now I weighed 5 charges of Swiss 3F from a flask spout I use for my 1858 Remington. The average of those 5 charges was 28.8 grains. I removed the spout, sealed the bottom and weighed 5 fills of water from it. The average of those was 28.9 grains.

That's not enough of a difference to matter in any way I can see, but that's just me. My 29 grain spout just hasn't been lying to me all those years as badly as I first thought. (I marked it before I had a digital scale; used an old balance beam scale of venerable age)

Steve
 
HMMMM!
I got a powder flask (not Colt, in fact no maker marks at all)with my 2nd Gen. Colt 1851 Navy and it threw too much powder for the Colt, so I cut the end of the spout down a bit to fill the chamber with enough room for the ball to seat and compress the powder. This was done by look and guess both in the spout and the chamber before I whacked it off. When I found the consistant level by sight in the spout I marked it and cut it off at the mark. Wanna quess the grn's? 28.8 when I weighed it and just over 28 when I measured by volume in my powder measure. I use less for CAS and target but not much less as this Colt shoots with the dropped load from the powder flask.
I use 28-30 grns in my Remy 44's. This is FFFG Elephant BP and I'm down to my last 1/2 can of it. So I'm going with Graf's or maybe Swiss soon.
 
Screw the unmarked spouts on your flask. Fill it then pour it into the adjustable measure. Adjust the measure to full and check the scale.

The adjustable measures I've owned in the past were either marked in 5 or 10 gr increments. For most rifle loads a 5 gr step can make a small difference in group size when tweaking your shooting load, but 10 gr steps are pretty much adequate.
 
Complicating the answer

"Screw the unmarked spouts on your flask. Fill it then pour it into the adjustable measure. Adjust the measure to full and check the scale."

Just do this. Everything else is complicating the process. If you don't want to do this then just guess. It does not matter if it is a 18 grain load or a 24 grain load as long as it is an accurate load. The numbers assigned just muddy the water. Use what works and forget the numbers. (that is for revolvers which can not be loaded too much as there is a finite amount that can be placed in each chamber.)
 
I have multiple guns that prefer different charges. I have multiple spouts, and multiple flasks to screw them into.

Why wouldn't I want to know which measure is which, and which ones match each other?:rolleyes:
 
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