Weighing Pyro and T7 charges

[tacotime]

Got two black powder measures and they spit out different amounts of powder when set at the same volume.

To find out which is right, I want to weight the powder from these two. Does anyone know the weight of a volume grain of Pyrodex and T7? "I gots to know". Thanks.

[Mike Brooks]

Don't waste your time. Gift that powder to somebody else and buy the real thing.

[Hogdaddy]

Pyro 70gr by vol=52gr average by wieght,, Just tried it two days ago ; ) PD Don'd know about Trp 7
H/D

[hylander]

Don't waste your time. Gift that powder to somebody else and buy the real thing.

That still won't tell him which powder measure is correct.
Just weighed some FF 777 with a know volume measure.
50gr. volume weighs 41.2gr. on the scale

[Omnivore]

Tacotime; You don't say how far off the two measures are from one another. The best test would be to get some BP and a scale and see which one throws the indicated weight of BP. Trouble there is; different granulations and different brands of BP will have slightly different densities, and so the volumetric method is only approximate anyway. Furthermore, try weighing charges of the same powder from the same measure several times and you'll find that the charge weights can vary as much as several grains depending on the dimentions of the measure and the filling technique. Ultimately, you settle on a load that works for you and don't sweat the minutae.

"This indicated charge from this measure works for me" is about as good as it gets. It you then choose to weigh that charge, I suppose you'd know something you didn't know before, but I don't know what use that knowledge would be to you unless you were weighing every single charge for the best consistency. Some long distance BP cartridge shooters do that, I suppose.

If at least one of your measures is adjustable and you want to use both measure for the same gun, then adjust one until they both throw the same charge. You can always adjust a non-adjustable measure by cutting it down, so cut down the one that throws the heavier charge until the two match. Or just use one of them and you'll have reasonably consistent charges.

I took a set of spouts for my revolver flask, weighed several charges of real BP from each one, took the average and marked each spout with that number. So now I know the actual average weight of BP (Goex 3F anyway) that each spout throws. It's nice trivia and all, but I still can't shoot any better.

[tacotime]

Well, not sure exactly how different, but the flask spout marked 40gr filled up the 40gr tube gauge and overflowed. The flask shutoff was not stuck open. So I switched to a 35gr spout, since the previous 40gr tube gauge was producing good loads, and I needed a flask to carry in the field. But the smaller 35gr spout loads appear not a consistent.

I found a table giving approx. weights of various Pyro and 777 charges, so I can use that to check the two. Like said, I guess the number is irrelevant once you find a good load and can duplicate it.

Now that I think of it, I guess I can check these charges using the Lee cc dippers, and a conversion factor to get from cc to grains of volume.

[starmac]

I may be understanding this wrong, but are you using two powder measures that are not the same, or those changeable tubes on a flask. I never considered those tubes to be much more than a funnel myself.

[fouronesix]

Now that I think of it, I guess I can check these charges using the Lee cc dippers, and a conversion factor to get from cc to grains of volume.

It all started way back in the early to mid-70s when they decided to handle Pyrodex on a BP volume "equivalent" basis. This mess has continued since. They should have just standardized all the load data based on grains- smokeless, black powder, substitute, whatever. After all, grains (weight) had been and continues to be the most widely used system in the US. BTW- There is no such thing and never has been- "grains of volume". Of course then Lee has to get into the act with their cc volume dipper measurement thing along with their bulk density tables. [smilie=1:

I think Omnivore's advice is as good as any to follow.

[bigted]

so this begs another question along the same line. what does say a 3 or 4 grain difference in charge weight do to accuracy in a front stuffer?

this is the ONLY reason to squabble about the different weights of any given powder measure or powder type. we all know that accuracy begets accuracy as well as consistency is key to accuracy sooo...back to the question...what difference will a 3 grain difference in a charge weight be on accuracy ?

if there is no subtle difference in accuracy then who is to say what measure is correct? as long as the rifle likes what is being fed to it then all is well...correct? as always...allow the rifle tell what it wants and what powder it decides it wants and what charge of weight or volume it needs to provide the accuracy needs of the shooter.

how to arrive at this combination.......shoot shoot shoot..... then .... change 1 thing at a time till your rifle lets you know what is going to be the details of an accurate load column .

as for the original question...I would go to the internet and look up the company that makes the particular powder and read there literature on the particular's...most likely it will be on the container as well....but then the circle goes round...if your rifle likes what your feeding it then why question the exact grain particulars ?

[tacotime]

Once I find the right load, I want to be able to duplicate it in the field out of a small flask (with a cutoff valve) and with the correct volume funnel.

And I would like to know the correct volume so I could duplicate the load anywhere using any accurate powder measure.

Can't do it now because the tube measure with markings appears incorrect, or else the funnel is holding more volume than marked. I can dispense from the 40gr funnel and it overflows the tube set at 40gr.

Hodgdon did not specify the weight, I assume because it is not to be used for measuring the powder.

[Omnivore]

You're saying that your flask spout overflows your measure? I'd suggest taking that 40 grain flask spout and cutting it down 'till it throws the right amount to fill your other measure. For future reference, say for using some other measure, you can weigh, in grains, what you're getting with your current measure with that particular powder. Problem solved. CCs don't matter, nor bushels nor pints, nor any other volumetric measure, so long as you can duplicate your pet charge using a scale, and cut a spout to throw that amount.

BTW; the reason the substitute powder makers invented "grains by volume" was so the shooter didn't have to buy a new powder measure - he could use the same measure he always used and ostensibly get similar results with the new substitute powder as he got with black, thus it was very easy to try out the new powders. The substitutes were specifically engineered to work with existing powder measures, and so their actual weight could be safely ignored in favor of the shooter's existing powder measures. Makes perfect sense from a marketing perspective, and also to some degree from the shooter's perspective, as he doesn't have to keep track of different powder measures for different powders. Now in reality there may be enough of a differences in performance that the shooter may actually want to use a different volume of a substitute than for real black, so... But safety is still a factor-- If the substitutes required a vastly different volume compared to black, there could be a major over-charge if one were to accidently use the wrong measure for the powder. So yeah; a simple volume-for-volume substitute, by design, does make sense. Don't be too hard on them for coming up with it.

[fouronesix]

No arguing "why" they came up with the volume to volume equivalent. The problem is so many shooters still have little understanding of it- so seems to be point of constant confusion.

[Fly]

Get a Lee powder weight scale, $20.Weight your powder & it will give you the right measurement.
I then put that powder in a adjustable powder volume measure & record the volume.Works great.

Remember powder comes in one LB cans.Volume is not always the same I don't care what anyone tells you.

Fly:wink: