Powder Weight vs volume? New to purcussion.

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I have been weighing powder for a while due to the fact I've been reloading since 1970 and love precision shooting and loading. Which ever granulated powder you might choose, always start by measuring volume then weight it and log it in. I've had this argued over and over that it will not work. Just today I was weighing out 20 loads for the range and every time I use this method, start by volume measurement then pour it in the weigh scales. By weight I'm usually off .2 to .3 of a grains from the volume measure proving the very reason I weigh each shot prior to range day or hunting. This method works for me and many that have followed. Never confuse FFg and FFFg being the same weight because of density differences. Shoot safe!
The very title of this thread states NEW TO PERCUSSION
The OP states he measured out 75 grain (by weight) as a starting load. OF PYRODEX.
The load he thought was a light load is really very close to MAX load.
Not only did the OP not know that synthetic and real BP don't weigh the same, I'm pretty sure he has never heard of the Curtrich study of 2012. The max stated by the manufacturer of his gun is 110 gr.
What if the OP had decided to start with the max and work his way down?
His first shot in a 35-40 year old gun would have been 135% of max load - and that done through shear inexperience with black powder.
You are 100% correct - if you are going to weigh - start first with volume measure -then weigh it.
Talking to several new black powder shooters at the range - I have discovered that very few of them have any idea how to measure and properly load for black powder. When I see another black powder shooter show up at the range that I don't know and see them fumbling about - I go strike up a conversation with them, and offer all the help they will take to get off on the right foot.
The young man that runs this section of the range has actually asked a new to black powder shooter that shows up to NOT shoot on that particular day because he sees them struggling. His job is to keep the range safe and a newbie at the black art can be a hazard to themselves and others near them. He asks them to come back on Tuesday morning and get with me.
 
Some time ago, just to satisfy my curiosity, I set my measure to 100 grains and weighed that volume of four different substitute powders. My results are as follows . . .

Pyrodex RS -- 100 gr = 85.5 gr (very old can)
T7 fffg -- 100 gr = 86.6 gr
T7 ffg -- 100 gr = 73.3 gr
Black MZ -- 100 gr = 78.8 gr

Based on these results I have no desire to to weigh charges when shooting. There appears to be little point to it when developing loads. I find an adjustable measure consistent and more than accurate enough for my needs. And I always know when I'm in common-sense safety limits.
 
I have purchased a traditions .50 mountain rifle and after reading through some posts I have decided on patched round ball for michigan deer hunting. I am shooting pyrodex with a .49 roundball and 0.18 pre lubed patch. I am getting excellent accuracy (based on my limited experience) at 50 yards with what I am gonna call a 1 inch to 1 1/4 inch groups

Now to my question. I have heard back and forth between volume measuring powder and weight measuring using a scale. Does this really matter in any way other than possibly over charging?
I am currently shooting 75 grains wieghed out on scale of pyrodex. I put it into cheap BP plastic tubes to keep measured charges with me and they show between 95-100 grains of volume. I don't trust the accuracy of the tube measurements but would this be any risk of being over charged?

The very title of this thread states NEW TO PERCUSSION
The OP states he measured out 75 grain (by weight) as a starting load. OF PYRODEX.
The load he thought was a light load is really very close to MAX load.
Not only did the OP not know that synthetic and real BP don't weigh the same,

Griz,
IMO the facts and statements of the original post are being misrepresented and taken out of context.
He didn't say that he thought that it was a light load, only that he was weighing the charges for consistency but didn't trust that the graduations on the small tube.
He knew that the 2 types of powders didn't weigh the same because he had heard about the back and forth discussions over volume and weight measuring.
He obviously came up with a load that was about 25% less than 100 -105 grains which is an acceptable load according to his manual. --->>> https://www.traditionsfirearms.com/data/product_owner_manuals/CURRENT - FIT 7 Revised Final FINAL_1477335832.pdf

The sky is not falling as your last post would like to make it seem.
THE OP KNEW HOW MUCH POWDER HE WAS LOADING SINCE HE HAD PUT IT IN A GRADUATED TUBE.
He simply didn't trust the tube.
And those loading/storage tubes are small and make it hard to see how even the load is.
The OP has pride in precise loads for his new Mountain Rifle, and doesn't need to use a small tube to measure his loads with when he has a scale.
The OP did nothing wrong and everything right by asking for advice about how to use his scale to weigh the most accurate and consistent loads.
Why not stick to the topic about how create the most accurate loads like the competition shooters do?


LOL - there are always exceptions to everything. For the average shooter who is inclined to use synthetic powders weighing charges is going to get them in trouble as no two synthetics will weigh out the same when compared to volume measure.
I do weigh my PRS charges (those "others" using that "other" kind of propellant) down to .05gr. That's down to 1 or 2 granules for a cylindrical powder. When shooting out beyond 1K yards it's going to make a difference. But that's a different world, and we are talking black powder and open sights pushing unbalanced projectiles are much shorter distances.
 
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I would imagine that many of the long range muzzle loader competitors who participate in the MLAIC world matches also weigh their powder charges.
Weighing black powder charges is common practice for long range target shooters today, and was also done in the 19thC. This, for example, from The Scotsman newspaper 14 April 1864: “Weigh every charge of powder carefully before going to the rifle range; for, unless you attend to this, your shooting will be irregular.”

David
 
Weighing black powder charges is common practice for long range target shooters today, and was also done in the 19thC. This, for example, from The Scotsman newspaper 14 April 1864: “Weigh every charge of powder carefully before going to the rifle range; for, unless you attend to this, your shooting will be irregular.”

David
How many of these guys from 1864 weighed their synthetic powders?
The point to most of this conversation was the differences between synthetic and real powder.
Given the same volume - no 2 synthetic powders will (by weight) be the same.
The point is was it safe for the OP to weigh synthetic powder assuming it was identical to real powder?
The OP weighed a charge thinking it was minimal charge and wound up with a charge very close to the maximum rating of the gun.
For very experienced shooters - like the seasoned match shooters mentioned above - it's not an issue. THEY KNOW THE SCORE
For a newbee with his first gun and no experience or guidance - it could easily have been a personal disaster leaving him injured and possibly blind.
 
The OP weighed a charge thinking it was minimal charge and wound up with a charge very close to the maximum rating of the gun.

He did not think that it was a minimal charge because his loading and storage vial had graduated markings and he clearly stated that he used it to double check his load which was between 95 and 100 grains. See his post below:

In my theory it shouldn't matter same weight of 75 grains should equal 97.5 grains volume every time as well. I tried just going off the volume in the tube to match the ones I weighed out and still good results just kept it between 95 and 100. I was able to hit a 8 inch plate at 100 yard s 10 out of 10 shots so I should be well with in enough accuracy of deer. Not gonna shoot past 75 though, don't see much reason to push the limit.
-------------------------------------------------------------------------------------------------------------------
For a newbee with his first gun and no experience or guidance - it could easily have been a personal disaster leaving him injured and possibly blind.

While I understand your concern, even experienced shooters load double powder charges in their guns by mistake all of the time and it doesn't usually ever result in injury or blindness.
And even if a person did make a mistake weighing a sub. powder it would be much smaller and much less hazardous than a double charge which modern ML guns in good condition are designed to handle.
Anyone can get injured shooting at any time.
That's why it's recommended to wear eye and ear protection whenever shooting.

The Traditions sidelock manual says to follow the manufacturers loading recommendations for measuring since some sub. powders may be measured by weight.
For example, the Black Horn 209 loading data page for muzzle loaders clearly shows its equivalent volume and weight measurements at the top of the chart, --->>> https://www.blackhorn209.com/wp-content/uploads/2010/12/b209muzzleloaderdata.pdf

Volumetric Units (volumetric powder measure) 80 100 120
Weight in Grains (weighed on a scale) 56 70 84

And then at the bottom of the chart it clarifies the difference between volume and weight:
1 - Volumetric Units = Measured with a standard black powder measure, or Blackhorn 209 graduated charge tube. This IS NOT equal to weight in grains

That means that even a sub. powder company acknowledges that there is more than one way to measure powder, and that it can be measured by either volume or by weight.
Just be sure to do the volume to weight conversion.

It's just like VM Starr listed his shotgun loads in drams, a person needs to do the conversion.
1 Dram = 27.3 grains of BP
 
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Well Arctic, in your mind you cannot ever be wrong or give bad advice.
In my mind giving this kind of advice will get a new shooter into trouble and is bad MOJO.
Go for it though. You won't change my mind and I won't change yours. I'm never going to get anyone hurt. You - well, that's on you...
 
The point to most of this conversation was the differences between synthetic and real powder.
Yes, although that’s not what the OP asked. Oh, and I very carefully referred to black powder charges to avoid any confusion in my direct response to observation made by another correspondent.

Black powder and all substitutes are created to be measured with a volume device.
Whereas sweeping statements like this are incorrect and further fuel confusion.

David
 
Yes, although that’s not what the OP asked. Oh, and I very carefully referred to black powder charges to avoid any confusion in my direct response to observation made by another correspondent.


Whereas sweeping statements like this are incorrect and further fuel confusion.

David
The only confusion is how the product was intended to be used BY THE MANUFACTURER - The maker is not confused.
Only the people who claim to be EXPERTS (Here - hold my beer and watch this)
Don't get new to the black art shooters hurt -
1603321905681.png
 
Hodgdon's intent is clearly stated and important because in order for the company to claim it to be a direct replacement for black powder, Pyrodex absolutely does need to occupy the same volume in a volumetric measurer.

The manufacturer's instructions only reflect that if Pyrodex is weighed out then it's as an indirect replacement because the conversion needs to be done first.

People are smart enough to figure it out based on their age and experience.
Responsibly weighing out powder charges doesn't break any safety rules.
Of course newbies first need to be taught how to use a volume powder measure.
The OP was well beyond that level and weighed his powder charges in a responsible way.
 
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If you are trying to shoot for extreme accuracy FOR A GIVEN POWDER, measure out by volume 20 loads and weigh each one. Take the average weight and from then on weigh your loads to that number for that powder. IMO weight is more accurate for a given powder but is prone to a potentially dangerous error when changing powders.

I have taken elk with 100gr FFg loads and a .495 ball at 90 yards. It is more than enough for a deer. My hunting days are over but I would select 80 gr for eastern deer.
 
When I was hunting mule deer in Idaho and Montana and little fellas near Sacramento I used 75 grains BP by volume. All loads from a buffalo horn tip … even when I used Pyrodex [not often]. Never lost a deer nor did I ever leave a wounded one in the field. How? Why? Never shot at a deer over 60 yards, usually much closer. Love the stalk in moccasins. Just my 1 1/2 cents worth. Love this discussion though. Polecat
 
Out of curiosity, last night I filled my volume measure 12 times and then dumped it onto my scale. I used 3f Goex and an adjustable measure set at 80 grains that has the leveling cone on top.
First I filled the measure 6 times to the top, leveled it by swinging the cone into place, and then dumped it onto the scale. No tapping or anything. These loads averaged 77.5 grains by weight with an extreme spread of 2.1 grains.
Then I did 6 more, but tapped the measure twice after it was full to settle the powder (my normal method, for no particular reason other than habit), topped it off again, swung the cone into place to level it off, and dumped onto the scale. These loads averaged 80.1 grains with an extreme spread of 2.2 grains.
I do not care for subs so I didn't have any on hand to compare to. Just did it more for the curiosity of what the extreme spread would be when using a volume measure.
I think measuring by volume or weight is whatever a person prefers, as long as a weight is checked against a volume measure to ensure you don't exceed max charge by volume per manufacturer's recommendations.
With open sights and a fairly large front post reference, you could knock me over with a feather if 2 grains of variance ever showed up on a target with BP when I'm the one shooting.
 
Some target shooters use a long brass powder drop tube when loading to help prevent the powder from sticking to the side of the bore.
That could be another powder variance that target shooters try to control for.
Where the powder ends up if it sticks to the bore could depend on the shape of the powder chamber, and how much and what type of fouling and patch lube a person uses.
If the powder that sticks is very fine, then that could affect the variance a little more than if not using the tube.
Perhaps using a scale could help offset the affect of not using a drop tube.
Using both methods together would be more ideal and prevent a cumulative variance by not weighing charges.
And it wouldn't only help target shooters since many hunters use powder storage tubes.
It's sort of like weighing and culling round balls based on their grain weights.
It can give a person satisfaction and confidence knowing that they've done all they can to enhance accuracy, and it could translate into an additional point or two on a target, or bagging a game animal with a marginal shot.
When a projectile hits a vertebrae instead of being a clear miss, that's only a difference of an inch or two either way which could make or break a hunting season.
Admittedly these methods are usually performed as a labor of love, especially for the
non-competition shooters.
But if they enjoy doing it enough, it could turn someone into being a competition shooter.
:)
 
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Some time ago I did a measurement survey of my volume measures to see What the differences were for these various measures. Oh, my gosh, it was 19 years ago.
Powder BrandGOEXGranulationfffgCode:03-7799N001CDate:
20 July 2001​
Desired Weight
100​
GrainsMeasure
100​
Volume Constant
0.004031​
in3/grain
248.047​
NameCan ValveFinialGostomsky
0-120 Gr
Gostomsky
Settled
Hawken Shop70 Gr
Tip
Large
Swivel
0 - 200 Gr
NikkyNikky
Settled
Doc's
Swivel
0-120 Gr
Standard
Diameter
0.433​
0.433​
0.43​
0.43​
0.52​
0.49​
0.43​
0.43​
0.432​
0.453125​
Depth
3.13​
2.65​
2.907​
2.907​
1.017​
1.982​
2.75​
2.75​
2.909​
2.5​
Calc. Wgt.
100.0529​
96.79337​
104.7142741​
104.7142741​
99.39849951​
70​
92.70854255​
99.05891​
99.05891​
105.7633​
100​
Average
101.22​
97.08​
104.95​
106.64​
99.05​
67.18​
88.54​
98.24​
98.96​
103.58​
103.44​
Std. Dev.
0.722342​
0.610646​
0.903388682​
0.440201974​
0.748702582​
0.700476​
1.534202652​
0.598517​
0.414193​
0.816224​
0.616802​
Maximum
102.1​
98.3​
106.3​
107.4​
100.3​
68.3​
90​
99​
99.9​
105.2​
104.8​
Minimum
100​
96.3​
103.1​
106.1​
97.7​
66.2​
85.9​
97​
98.5​
102.4​
102.8​
Conf. Int.
0.837404​
0.707917​
1.04729036​
0.510322182​
0.867964157​
0.812056​
1.778587312​
0.693855​
0.48017​
0.946242​
0.715053​
Lower Limit
100.8013​
96.72604​
104.4263548​
106.3848389​
98.61601792​
66.77397​
87.65070634​
97.89307​
98.71992​
103.1069​
103.0825​
Upper Limit
101.6387​
97.43396​
105.4736452​
106.8951611​
99.48398208​
67.58603​
89.42929366​
98.58693​
99.20008​
104.0531​
103.7975​

I may have been pretty careful in my measurements as I held most of them to less than one grain standard deviation from the selected setting. (68% of my measurements were less than 1 grain.) The confidence interval means that I am 90% confident that the weight of the powder that I measured would be that many grains from the selected weight. The Large Swivel would pour up to 200 grains. In theory I thought I might have needed a lot of powder. In practice that just wasn't the case.

The measure that fit to a valve on a can of powder fit into the measure so the depth of the measure took into account the insertion of the valve into the measure.

The major take aways from all these measurements is that when developing a load for accuracy, use only one measure. My 70 grain antler tip was pretty consistent. Tapping the measure to settle the load will provide a more consistent measurement, but less than 1/2 grain different than unsettled.

GOEX 2fg was a little lighter and closer to the predicted weight compared to volume.
 
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