Black Powder Weight Qestion

Bryan Austin · October 31, 2009, 07:40:38 AM

If Goex FF varies in weight from one batch to another, where does "power" come in?

Do you get powder from volume or weight?

If I have at load 38gr, by volume, that actually weighs 37gr....and a load 38gr, by volume, that actually weighs 39gr, which volume load will be more powerful.

Good Lord I hope I asked that right.

Dick Dastardly · October 31, 2009, 08:42:11 AM

Part of the price in premium black powder comes from very tight quality control. ie., Swiss. The best answer to your question will be revealed by graphing bullet performance. I've found less difference in velocity from batch to batch than you might expect given the different loose density of powder from one brand. There's a bigger difference from manufacturer to manufacturer.

DD-DLoS

Driftwood Johnson · October 31, 2009, 09:46:33 AM

Howdy

Look at it this way. The bigger pile will have more power. However you measure it.

Blackpowder Burn · October 31, 2009, 10:01:23 AM

The "power" produced is a result of the amount of gas produced by combustion of the powder. The combustion reaction produces a known amount of gas for a given amount (mass) of powder. This is dependent on the mass, or weight, of powder, not its volume. So, assuming all other things are equal (type of wood used for the charcoal, ratios and purity of the ingredients, etc.) the power is determined by the mass of reactants. Thus, to produce an equal power load, you would load by weight, not volume.

That being said, none of it really matters much at the distances we shoot normal matches.

Delmonico · October 31, 2009, 10:10:40 AM

I had enough chemistry to be dangerous, more mass means more molly-cules, more molly-cules bein' changed around will mean more gas and more leftover by-products, provided the exact mix is used. Sometimes also the difference in mass in powders is the mouture content.

Springfield Slim · October 31, 2009, 12:57:29 PM

More is more, no matter how you measure, or don't measure. Fill up the case until you get some compression. Done. It doesn't matter what the number is, weight or volume, it is what it is. If it makes you feel better you can weigh it, measure it, but it won't make the cartridge work any better.

Bryan Austin · October 31, 2009, 01:14:34 PM

I'm just curious thats all.

Montana Slim · October 31, 2009, 05:10:14 PM

Only way to be sure is to Chrony the load....lot-to-lot, brand-to-brand, granulation-to-granulation will be a bit different.

Genuine BP is used in some military applications. Powder bought to these specs will have minimum burn rates and other properties.

Commercial stuff is simply made to commercial standards - all bets are off. Same for commercial ammo.

SAAMI standards are voluntary as well and don't exist for a number of available old-west cartridges/components.

Regards,
Slim

Frenchie · October 31, 2009, 10:01:58 PM

You and your firearm are not going to be able to tell the difference between 37, 38 and 39 grains of the same powder. IMO it takes at least a 5 grain difference to even begin to be noticeable, but don't hold me to that.

Bryan Austin · October 31, 2009, 11:01:13 PM

Still curious!

Angel_Eyes · November 01, 2009, 03:19:49 AM

Savvy Jack, here is an instance that may explain.
When I was very keen on competition target shooting with my ROA, I spent hours going up and down the powder scale, looking for the perfect load.
When I thought I had found the most accurate load, ( 32.5gr of Tri-angle (blasting powder supplied by a friend in demolition)), I stuck to it for years and did very well in comps.
Later, I happened to want to load some 45Colt for a project and used the flask and spout to fill some trial cases.
When I weighed the amounts, I found that they were under weight by as much as 2 grains, but this had made no difference to my point of impact, still very accurate.
After that I just carried on using the same spout, no matter which batch of powder I had been supplied.

P.S. I found that 32.5 grains was not a good load in the case for 45 colt and had to increase it so it could leave no airspace and be compressed to gain any measure of consistency.

Hope this helps in some way,,AE

Bryan Austin · November 01, 2009, 07:55:37 AM

So I am to understand that weight = more power, regardless of application (hunting, CAS, defense, accuracy). I know, it was kind of a dumb question but I had to ask!

Not all my questions have to do with CAS.

john boy · November 01, 2009, 11:25:34 AM

Jack, Springfield Slim's explanation was so simple, even a cave man could understand it ...

QuoteLook at it this way. The bigger pile will have more power. However you measure it.

QuoteI know, it was kind of a dumb question

Yes, it was a dumb question and was explained several ways. Believe at this juncture in your learning curve, you should buy some reference books about reloading and ballistics ... and start reading. Then you won't have to ask the dumb questions

Bryan Austin · November 01, 2009, 04:18:18 PM

I can ask dumb questions if I wanna! What else would you be doing if not answering my dumb questions? Never mind...don't answer that dumb question.

Yeap just as I spected. 38gr(volume) of one batch of goex weighing 37gr is less powerful than 38gr(volume) of another batch weighing 39gr.

Cuts Crooked · November 01, 2009, 05:25:31 PM

The onliest dumb questions 'round these parts is the ones ya don' ask! Iffin ya don' ask, y'all will always be "dumb".

Fairshake · November 05, 2009, 09:56:38 AM

Jack, I think that a lot of confusion has been brought on by the advent of the play like powders. They started using the terms to load by volume. If you do research on the BP loads of old you will find that they loaded by weight and not volume. I have found that BP has to have a lot more increase in grains to make or see a difference. 35 grs will give the same results as 39 grs and so on. That's why you can take a powder flask with a fixed tube and run different powders and still have the same results. This all has to do with the nature of BP when it's ignited and it's burn rate not with volume loading.

Bryan Austin · November 05, 2009, 04:54:31 PM

Quote from: Fairshake on November 05, 2009, 09:56:38 AM
Jack, I think that a lot of confusion has been brought on by the advent of the play like powders. They started using the terms to load by volume. If you do research on the BP loads of old you will find that they loaded by weight and not volume. I have found that BP has to have a lot more increase in grains to make or see a difference. 35 grs will give the same results as 39 grs and so on. That's why you can take a powder flask with a fixed tube and run different powders and still have the same results. This all has to do with the nature of BP when it's ignited and it's burn rate not with volume loading.

Thanks Fairshake!

I have yet to compare with Goex BP but I have done a test with the heathen Pyro-P sub. I found that 37gr (by volume) gives me a consistent 378 ft lbs of energy while 38gr gives me a consistent 413 ft lbs of energy. I would like to know what the chamber pressures are though!

And for some other folks...this has nothing to do with CAS loads

Bryan Austin · November 05, 2009, 05:20:34 PM

On average my current batch of Skirmish FFF and Goex FFF

40gr/V of Skirmish FFF = 38.2gr/W
40gr/V of Goex FFF = 39.6gr/W

I'd say that pretty close?

john boy · November 06, 2009, 09:33:29 PM

Jack, your volume to weight numbers for the Goex FFFg are most interesting. What is the lot number of this powder?
Here's why:
39.6/40 = a density of 0.99
Goex is normally less dense - for example 3 different lots of Goex FFFg that I have poured in a Tresco volumetric measure to 100 cc (or 100grs if you like) and then scale weighed:
Scale Weights
94.4gr - Lot 99JY20C = 0.944 density
92.5gr - Lot 03 46 07Nov03B = 0.925 density
91.6gr - Lot 03 56 08Nov2B = 0.916 density
(averages of 5 drops for each lot)

Your 0.99 density is the highest I have ever heard of for Goex FFFg. Measure 100 cc volume of your powder and then scale weigh it, if you would. Don't compress the powder in the volume measure - just pour it in from a couple of inches above the opening

Bryan Austin · November 07, 2009, 04:34:05 AM

Quote from: john boy on November 06, 2009, 09:33:29 PM
Jack, your volume to weight numbers for the Goex FFFg are most interesting. What is the lot number of this powder?
Here's why:
39.6/40 = a density of 0.99
Goex is normally less dense - for example 3 different lots of Goex FFFg that I have poured in a Tresco volumetric measure to 100 cc (or 100grs if you like) and then scale weighed:
Scale Weights
94.4gr - Lot 99JY20C = 0.944 density
92.5gr - Lot 03 46 07Nov03B = 0.925 density
91.6gr - Lot 03 56 08Nov2B = 0.916 density
(averages of 5 drops for each lot)

Your 0.99 density is the highest I have ever heard of for Goex FFFg. Measure 100 cc volume of your powder and then scale weigh it, if you would. Don't compress the powder in the volume measure - just pour it in from a couple of inches above the opening

I'll find out this morning!