BP question

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gasmandave

gasmandave

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BP is measured by volume.
So 30 grs of 2f is less then 30 grs of 3f power wise and 30 grs of 4f is more powerful than 30 grs of 2f.

Is that a correct assumption?
 
The finer the powder the more granules there will be, so the more surface area to ignite and burn which means the load burns faster. There's still 30grs of 2, 3, or 4F by volume, but it's more dense because of less air space between granules. Now, I just measured 100grs of GOEX, 2F and 4F. The 2F weighed 100.3grs, the 4F 98.7 grs. I would have thought just the apposite. Well, it was close enough to both being the same -for me anyways.
 
paul harm said:
The finer the powder the more granules there will be, so the more surface area to ignite and burn which means the load burns faster. There's still 30grs of 2, 3, or 4F by volume, but it's more dense because of less air space between granules. Now, I just measured 100grs of GOEX, 2F and 4F. The 2F weighed 100.3grs, the 4F 98.7 grs. I would have thought just the apposite. Well, it was close enough to both being the same -for me anyways.
Click to expand...

That's interesting that you discovered such an anomaly.
Perhaps there's more residual moisture content in the 2F from the manufacturing process which is intended to give it more strength.
I wonder if a drop tube would make any difference as to how much each would settle into the powder measure.
 
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AAAAAAAAAAHHHHHHHHHHHHHH!!!!!!!!!!!!!!!!!!!!!!

Grains is a unit of weight, or mass. It is not a unit of volume. The idea of grains/volume is a construction made up so Black Powder subs such as Pyrodex, which weighs less than Black Powder, could be safely loaded.

If you weighed a charge and it weighed 100.3 grains, then that is what it weighed. If you weighed another charge and it weighed 98.7 grains, then that is what it weighed. Period.

Sorry, I sometimes go off the rails a little bit when this stuff comes up.

I suspect you are probably using a volume type measure that is set to 100 grains. When you weighed the charges, you found that they did not weigh exactly 100 grains. Were you using a powder measure similar to this? The sliding bar at the end is graduated in 10 grain increments. All this means is that at some point somebody in the bowels of a factory weighed out a bunch of charges, and figured out where to mark the lines for each volume of powder. It ends there.

measure-1.jpg




Yes, the smaller grains of a finer granulation of powder will generally pack more into a specific volume than the larger grains of another powder.

It might interest you to know that not all Black Powder weighs the same either.

I put this chart together a bunch of years ago, for the actual grain weights of some of the Black Powders I was using at the time. It refers to the Lee Dipper sizes, which are graduated by Cubic Centimeters, an actual volumetric unit of measure. Sorry, I have no FFFFg data, have only used it in the pan of a flintlock, never in cartridges.

BlackPowderWeights_zps5bea048d.jpg




Why did your measurements go against the usual calculations? No idea, I was not looking over your shoulder. Did you average a bunch of charges? Did you level the charge consistently? Powder weight can also vary by lot number. One lot can easily weigh more than a different lot.

As a rule of thumb, for my Black Powder cartridge loading, you will achieve somewhere between 60 fps to 100 fps more velocity from a 3F charge than you will from a 2F charge. All other things being equal.

I think I would hesitate to say one granualation is 'more powerful' than another. I would probably say one is more energetic.
 
I've been doing this stuff for 48 years and understand and knew all the stuff you bring up [ except your chart ]. No, I only did one measure, and I just wiped any over load of powder off the measure [ like you shown ] with a card. All I observed was BP weighed about the same as it's volume equivalent whether it was 2F or 4F. It doesn't really matter to me now, I just care what charge by volume gives me the best group. Seeing how both the 2 and 4F came from cans that had been opened I don't know how many times, maybe the 2F powder picked up more moisture from the air, so it weighed more. All I did was disprove something I had always assumed that the 4F would weigh more than 2F with both having equal volumes. I would think " more powerful " is more of a blue collar way of saying " more energetic. " When I'm loading BP in my shotguns, my normal load is 82grs of 2F or 70grs if using 3F. Have I ever checked velocities - no, it's just what a number of us have settled on as working pretty good. Driftwood, one of the definitions of mass IS volume. Your opening statement needs a correction. :) I look at it this way - I'm measuring muzzle loading loads by volume, not weight, and really could care less what it weighs. I'm kind of sorry I ever weighed the two.:oops:
 
Paul, I have always done the same as you on any of my black powder cartridge stuff. When it comes to my 45/70 I stuff as much powder in the case as it will hold and still seat the bullet. Same thing with my shotgun, I stick with components that work and I don't worry about what powder weight is. I played around with black powder loads in a 38 short and wimpy years ago and it was at best wimpy. I also loaded it with Unique and it was still wimpy, just cleaner. I guess the point is not to over think this stuff and go shoot.
 
Driftwood Johnson said:
Grains is a unit of weight, or mass. It is not a unit of volume. The idea of grains/volume is a construction made up so Black Powder subs such as Pyrodex, which weighs less than Black Powder, could be safely loaded.
Click to expand...

No Idea Where You Got This ??? :confused: :thumbdown:

Original gun powder [black powder] when it began to be used in small arms, was measured based on the Avoirdupois system where the pound was divided by 16 into ounces, and the ounce was divided by 16 into drams, and thus the pound defaulted into 7680 grains. Elizabeth I, adopted the Troy system smallest unit of measure, the "grain" and when she switched from the Troy 12-ounce pound (5760 grains) to a pound with 16 ounces...it made the pound 7680 grains.
.
The new system under Elizabeth was very similar to the Apothecary's Weight system which in England was aligned in part with the old Troy Weight system. Although the Apothecary's system used liquid ounces and measured by the volume of that ounce, it's smallest unit was the minim, which was equal to the dry unit of weight, the grain. Over time as small arms developed, using volume containers based on fluid ounces to measure gunpowder came into effect, and this was centuries ago....long before Pyrodex. Since grains and minums were the same, it was easy to adapt volume measures of one scruple, being 20 grains, or variations based on the smaller grain/minum to use when loading gunpowder.

BUT when smokeless was invented it was discovered that there was confusion over loads because the new powder was not interchangeable, AND because a lot of the previous measuring devices were not very precise. The imprecision didn't matter with black powder, because a variation of a grain or two from a weighed amount vs. a volume amount didn't make a huge difference in pressure or velocity....i.e. if you wanted to shoot 40 grains of powder by weight, but your measure tossed 45 grains because the amount was "rounded" instead of a "level measure"..., normally was not a problem. Plus black powder differed in weight from maker to maker depending on formula, the ratios of the three components varied from country to country, but due to the inefficiency of BP as a whole, it didn't matter enough to the small arms shooter.

With smokeless powder, however, being off by a few grains might be a real pressure problem, and confusing the two powders was even worse. Imagine the old .44-40 round using black powder at 40 grains, being reloaded with 40 grains of cordite. :what: While at the same time the .30-30 cartridge came onto the market not using 30 grains of black powder, but 30 grains of smokeless powder.

So today, as in centuries past, one loads the antique techonolgy with a measure based on volume using the liquid minim which was once equal to the weight of the grain. Over time the Avoirdupois system was made more precise, the ounce went from 480 grains to 437.5 and the pound went to 7000 grains. So today the Apothecary ounce is different from our Avoirdupois ounce. ;) The grain is still, however the grain, and we are now so precise that we measure in 10ths of a grain when loading smokeless powder..., by weight.

LD
 
A "grain" is a unit of measure by weight. Scales are calibrated to a high standard just for such measuring. When I develop a load a BP load I use weight by a scale in 5 grain increments. I then make a custom "measurer" to hold that developed load amount and THAT custom "measurer" is used as "by volume" in grain equivelant weather it is another brand of BP or a substitute. 100 grains of 2f will have less energy than 100 grains of 4f due to surface area. same load measured by volume can vary considerably.
 
BP has always been measured by volume but the "grain" terminology came about as a way to talk about charges. I've been shooting BP since the 1960s and make my own fixed measures; mostly out of antler. I'll start off with an adjustable measure to find my best load and then make the antler measure to hold just that amount. Only then I might weigh the charge just to see what weight I'm using.

Powder brands vary quite a bit. Some simply have more power potential than others. 2F and 3F are the most common with 4F used only as pan prime in flintlocks. And yes, the finer the powder the faster it burns; all things being equal which they rarely are.
 
gasmandave said:
BP is measured by volume.
So 30 grs of 2f is less then 30 grs of 3f power wise and 30 grs of 4f is more powerful than 30 grs of 2f.

Is that a correct assumption?
Click to expand...

Someone may already have said this but by my understanding 2f is slower burning than 3f but not more powerful per se to clarify, out of a very short small caliber barrel 3f or 4f will give the most percieved power but put 3f or 4f in a larger caliber longer barrel and you will get a faster pressure rise yes but power out the end of the barrel would be better if it was the same quantity of 2f.

Comments?
 
That's correct. The same weight of BP has the same chemicals, the same reaction. Fineness affects burn rate. Finer powders will ignite faster and burn more rapidly. I use 4F as propellant in flintlock pistols, the shot development is much faster than 3F.
 
Paul Harm:

I want to apologize to you for coming off as a jerk.

Loyalist Dave:

Thanks for your knowledgeable history of weight measurement systems.

For the record, although I started messing around with Black Powder in 1968, most of my experience with it has been in the last twenty years with Black Powder cartridges I load for CAS.

I too load my Black Powder cartridges by volume. The chart I posted is just a reference I use so I can have a general idea of what my typical charges weigh. When I load most of my cartridges I am using a Lyman Black Powder measure which portions out powder by volume, not by weight. For a few cartridges I simply use a Lee dipper set, or custom dippers I make from cartridge cases. And of course, when I load Smokeless, my Hornady powder measure portions out charges by volume too, as does just about every other powder measure. I do double check the charge on a scale before making a bunch of Smokeless ammo.
 
No apology needed. Sometimes things don't sound [ is that possible on the internet ? ] or come out like you intended. I find your post very good. Now, about that mass/volume thing. In my dictionary one of the words they use to define mass is volume. :) Just thought you'd like to know for future reference. :rofl:
 
paul harm said:
Dave, that was pretty good. I must say, some of you guys dive deeper into this stuff than me. Thanks for the history lesson
Click to expand...

You're welcome, but it was just that years ago I got confused when hearing old terms and reading those terms in old books, such as drachm and dram, (you used to see "dram equivalent" on all boxes of shotshells), I had also heard of a "wee dram of whiskey" . Plus there is "square load" and also the old "parts" system of formulas, i.e. "black powder is 15 parts of saltpeter, 3 parts sulfur, 2 parts charcoal" ....parts?.....So what the heck did they all mean? Then I ran into the different measuring systems, then the different ounces of Troy vs. what we use today, and wanted to know "why".... found it was arbitrary, government deciding on a "standard" and that the standard goes waaay back.
<shrug>

LD
 
Loyalist Dave said:
Plus there is "square load"

LD
Click to expand...

Square load is one thing I don’t have an accurate definition for. I read some feel it’s an equal volume of powder to shot, but in others it’s more than that, being as tall a column as it is wide. Do you happen to know the actual definition?
 
Howdy Again

A Square Load in a Black Powder shotgun shell is the same volume of shot as powder. Putting in more powder (by volume) tends to blow the pattern. Putting less powder (by volume) than shot is fine.

My typical Black Powder shot gun load is 4.3CC (about 66 grains) of Schuetzen FFg, a 1/8" Circle Fly Over Powder Card, a 1/2" Circle Fly Compression Wad, 1 1/8 ounces of #8 shot, a Circle Fly Over Shot Card, all stuffed into a Remington STS Hull with a Winchester 209 Primer.

Shotshell%20Components_zpsrl71zpfq.jpg




Yeah, it is a lot of work making them, most guys use a modern plastic wad, but the heat of BP burning tends to leave strings of melted plastic in the bore. The only reason I put in the over shot card is because with this recipe, my crimps tend to be concave and a few pellets can escape at the center of the crimp. This is a bit less than a Square Load, the powder charge actually amounts to about 2 1/2 drams, but 4.3CC is the biggest dipper in my Lee set, and this knocks down everything I point it at anyway.

P.S.

The formula for Black Powder has varied slightly over the centuries. An old Explosives Textbook of mine says in addition to several other earlier formulas, a British contract in 1635 called for 75% Saltpeter, 12.5% Charcoal, and 12.5% Sulfur. Later formulas were 75% Saltpeter, 15% Charcoal and 10% Sulfur. This is the formula the US Army settled on sometime in the 19th Century. I will never forget my Dad, who was a chemist working for Hercules Powder Company in WWII telling me the 75%,15%,10% formula when I was a kid, because he knew I was going to be experimenting with it anyway. Couldn't find any real Saltpeter (Potassium Nitrate) had to settle for the Sodium Nitrate that came in my chemistry set. This stuff did not explode, but it made pretty good rocket fuel.
 
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Mine are pretty much the same as Driftwoods except sometimes I cut a shell down so less shot and or wads are needed. shells 002.JPG There's a 10ga 2 1/2, 12ga 2 1/2, and 12ga 2" shells, all roll crimped. For the middle one, 70grs of 3F, .135 OP card, 1/2" cushion, 7/8oz of shot, and the .028 OS card. I've found in just about any shotgun game that 3/4 or 7/8oz of shot is more than enough. Also easier on my old shoulders.
 
My pipes. I smoked for around 60 years, mostly my pipes. I have to have around 25 of them right now - all sitting in drawers. Had to quit. Started on Chesterfield Straights, Lucky Strike, Paul Maul, Camels, anything without a filter. Both grandfathers and my dad smoked pipes, so I went to them. My problem is I inhaled them. Final got short on my breathing and didn't want to have to cart around a oxygen bottle. Still miss smoking them, but glad I quit.
 
After smoking mostly Marlboro and Camels for 26 years I finally quit. So glad I quit! Now it’s an occasional cigar.
 
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