BP Charge measureing accuracy

[AtlLaw]

Y'all know I've been having a bunch of fun playing around with my 2 new revolvers.  One point on my learning curve involves, suprise suprise,   the actual measureing of powder and finding a favorite load.

Now I've always thought this is pretty easy with BP firearms... rifles to be exact.  One powder, one projectile, one primer, mostly just pick a powder starting charge and work up in 5 gr. increments till you find a charge you like.  Load development done!     Of course there is more then one maker of BP and caps, and some people use other then RB's, but we be talking generalities here!   

I have a tube type adjustable powder measure I've used for decades.  Never worried about accuracy when measureing 70 or 80 gr. of FFG HB or a BP substitute volume equivalent. 

But I figger I got to be a little more precise when working with an approximately 5 gr. min/max spread of FFFG.  That's my own spread designation BTW; 20 to 25 gr. for the .36 cal. (20 gr. recommended re: DGW) and 25 to 30 gr. for the .44 (28 gr. recommended re: DGW).  So I dug out my balance beam scale and checked the accuracy of my measure using Goex FFFG powder.     

Low and behold, the measure is right at 2 gr. low!     20 gr. from the measure is 18 gr. in the scale, and 30 gr. from the measure is right on 28 gr. in the scale!

Geeeeeze!  Now I gotta go out and shoot my baseline charges all over again!      Will the work never end...   

Okay, my point... um... question!     In smokeless reloading I initially check the performance of my loads in .5 gr. incriments and finalize the selection of a load based on one-tenth of a grain evaluations.  What do y'all consider a significant load change for FFFG?  one-half grain?  One grain?

[Flint]

You sorta mentioned it in your question..   The accuracy of weight or volume required depends upon the size of the charge to begin with.  With a rifle loading 70 or 80 gr, the error factor is pretty wide to make a difference, pribably 1 or 2 gr window, and just the act of pouring into a measure can vary the charge from one load to another.

A revolver load of 20 to 30 gr is more sensitive to variations, just because of the percentage of the total one grain is.  A powder flask charge can depend on how much of your finger pushes into the spout when you are using it.

The actual weight of a charge for any volume can vary from can to can, brand to brand, granulation, and probably humidity and temperature.

[simonkenton]

Put away the scale. This isn't smokeless powder.

You are making this too  complicated, but, it sounds like you are having fun.

[mcwoodduck]

I have a tube type adjustable powder measure I've used for decades.  Never worried about accuracy when measureing 70 or 80 gr. of FFG HB or a BP substitute volume equivalent.  


Low and behold, the measure is right at 2 gr. low!    20 gr. from the measure is 18 gr. in the scale, and 30 gr. from the measure is right on 28 gr. in the scale!

Geeeeeze!  Now I gotta go out and shoot my baseline charges all over again!    Will the work never end...  

Altlaw,
The measures are based on Volume and not weight.
If 18 Grains on the scale is 20 grains in the volume measure than don't worry.  You are going to load from the volume measure and not the scale.
If it makes you feel better think of the numbers on the adjustable measure like the bushing numbers in a MEC press.  Depending on the powder you are using will give you different weight charges.  The tripple F will give you one weight, Double F will give you another and Pyrodex P and then RS will give you others.  The larger the grain the lighter the load as well.  Also You and I using the same powder and measure will get different weights in how we measure from the flask.  I put my finger over the 20 grain tube, Open the flask and slam the powder into the measure with a flick of my wrist and close the flask.  Also the fatter I get the more the my finger takes up room in the measure.  
As long as you are consistant in your loading ritual and measure the same way each time you will have consistant groups.

[AtlLaw]

sounds like you are having fun.

Heck, I'm having a blast!     So to speak...     Anytime I can play and experiment with something and learn something I get excited!  Shoot, you shoulda seen me when I reached puberty!    

The measures are based on Volume and not weight.

Is that correct for the BP itself?     I know it is for the substitutes but always thought the BP was the constant... 

I remember in going to smokeless powder from black in shotguns we got new powder measures that we could use to load a "Drams Equivalent" charge.  The amount of smokeless powder that would equal a given amount of black powder.  From that memory I have always assumed that the weight or volume of black was the base line.   Any amount of another type of powder was an equivalent.  Hence a volume equivalent charge of, say 20 gr. of Pyrodex by volumn, equals 20 gr. of BP by weight.  Kinda like measureing cups are in 1/4 cup, etc. but can also converted to be used to measure fluid ounces.  One is volume, one is weight.  The volume of the 1/4 cup of flour is equal (by whatever criteria) to the weight of a quarter cup of water; 2 ounces.  And I understand you cannot bake with water or boil with flower!    

As long as you are consistant in your loading ritual and measure the same way each time you will have consistant groups.

AH HA!  Herein lies the answer!      Once I find out what charge gives me the best accuracy, what difference does it make HOW I measure it!    And, as long as I refer to the charge as "by volume" or "by weight" I'll be accurate in relaying the amount even if the numbers don't match!   

[mcwoodduck]

[
Is that correct for the BP itself?    I know it is for the substitutes but always thought the BP was the constant...  

I remember in going to smokeless powder from black in shotguns we got new powder measures that we could use to load a "Drams Equivalent" charge.  The amount of smokeless powder that would equal a given amount of black powder.  From that memory I have always assumed that the weight or volume of black was the base line.   Any amount of another type of powder was an equivalent.  Hence a volume equivalent charge of, say 20 gr. of Pyrodex by volumn, equals 20 gr. of BP by weight.  Kinda like measureing cups are in 1/4 cup, etc. but can also converted to be used to measure fluid ounces.  One is volume, one is weight.  The volume of the 1/4 cup of flour is equal (by whatever criteria) to the weight of a quarter cup of water; 2 ounces.  And I understand you cannot bake with water or boil with flower!    

[

[/quote]
Altlaw,
While the saying a pint's a pound the world around it is only true for water.
Wait a 1/4 cup of water is the standard but a 1/4 of sand is still a 1/4 cup but will weigh a lot more than the water and a 1/4 of mud will weigh even more.
Depending on how fine a grain you have you may be able to pack more weight into a 1/4 cup than 2 oz or 875 grains.  
I had someone that wanted to reload on my stuff to a certain load.  I was loading Win Super lite at the time and 1 Oz loads.  He changed it for 1 1/8 oz loads and Red Dot.  he changed the machine back but used the same bushing.  I was now getting 38 grains of Win Super instead of the 22 he was with Red Dot.  It cracked the stock on my SKB.  OH the one load I could find for 3.5" 2 oz loads only used less than 30 grains of Win Super lite.
By volume you want to load 80% of pyrodex for black.
So a 20 grain 36 cal load of FFFg is going to be 16 grains by Volume of Pyrodex P.
As Pyrodex RS is a larger grain and does not pack in a tight as the smaller P if you load 64Grains of RS into your rifle it my weigh 58 grains on the scale if you load 64 grains (My RS .50 load for round ball) of P it will weight 60-62 grains (don't hold me to the number but they are close from memory)
Again if you are loading consistant the same amount and not over loading the gun you will not have a problem.
I will not even get into the whole Part about the balls not being perfectly round and the flat spots are effecting accuracy as well as not all of the balls weigh the same.  So if the charge in one cylinder is off by .1 grain and the ball is off by 10 grains they will shoot to the same point or at least more accuratly than you will be able to at 25 feet. (not saying anything about your shooting)  Then ther is how much Stuff is in the cap are the holes all the same on the nipple..... I can go on and on.
Heck I had 1/2 a cylinder with round ball and 32 grains of Pyrodex P in my Remington 58 and 36 grains of P with 180 grain Buff conicals in the other three and they all shot into the same 3" group at 30 feet.  3" is good for me two handed with the smoke box.

[coyotejoe]

You've got it AtlLaw, use your volume measure to find the best load and then just continue to use that same volume, the actual weight is just incidental information of no real value.

[AtlLaw]

<major snippage before and after this line...>
So a 20 grain 36 cal load of FFFg is going to be 16 grains by Volume of Pyrodex P.

 

I read your whole post McWoody... several times...  I still can't make your bushing analogy relate to the issue here.  

So I picked out the line I quoted above because I guess it means you agree with me cause I think that that is what I said; weight vs. weight by Volume.  

My head hurts...    I like what CJ said.  Since the inception of substitute propellents everything is measured by volume anyway.  The origin of the measurement doesn't make any difference...

I wonder...    How much BP will I get if I tell my supplier I want a pound of FFFG ... by volume?    OH!  OH!!    Or an amount of FFFG equal to the volume equivelant of a pound of Pyrodex!  YAH!  That's the ticket!  

I need a drink... 

[mcwoodduck]

<major snippage before and after this line...>
So a 20 grain 36 cal load of FFFg is going to be 16 grains by Volume of Pyrodex P.

 

I read your whole post McWoody... several times...  I still can't make your bushing analogy relate to the issue here.  

So I picked out the line I quoted above because I guess it means you agree with me cause I think that that is what I said; weight vs. weight by Volume.  

My head hurts...    I like what CJ said.  Since the inception of substitute propellents everything is measured by volume anyway.  The origin of the measurement doesn't make any difference...

I wonder...    How much BP will I get if I tell my supplier I want a pound of FFFG ... by volume?    OH!  OH!!    Or an amount of FFFG equal to the volume equivelant of a pound of Pyrodex!  YAH!  That's the ticket!  

I need a drink... 

Sorry It made sense in my Pea brain at the time.
I think I was saying that the different grades of powder as well as the subs will all weight out differently with the same volume.  And was trying to use the Mec reloading bushings as an example of how 22 grains of one powder is 38 grains of another due to the smaller size granual.
Some times I need to look at the question and realize you want to know what time it is rather than how the watch works or the history of telling time.

[stubshaft]

The manufacturers have sure picked up on this.  That's why Blackhorn is sold in 10 oz. jugs.  Because it is supposed to measure one pound in volume.

[AtlLaw]

I was saying that the different grades of powder as well as the subs will all weight out differently with the same volume.

Ain't no doubt about it!    What's that called ...    density per CC? 

And was trying to use the Mec reloading bushings as an example of how 22 grains of one powder is 38 grains of another due to the smaller size granual.

Another example along the same line would be a set of Lee dippers.  The very old set I have has a sliding scale attached to the box that tells how many gr. each dipper holds of what powder.  Used them for a long time when I loaded shotgun shells outa the trunk of my car at skeet matches.   

The manufacturers have sure picked up on this.  That's why Blackhorn is sold in 10 oz. jugs.  Because it is supposed to measure one pound in volume.

Is'at right!     So 10 oz. of B'horn equals the equivalent of one pound of (I assume) FFG BP!?  Good business decision...    Tell the customer that they are getting the equivalent of one pound of powder (as many shots/loads as a Lb. of BP) while saving 6 oz. per pound!  What a profit inducer!      Ain't this equivalent stuff great!   

[gcrank1]

Ive messed around with the 5gr, V changes for rifle and smoothbore and about (eyeball on the charge tube scale) 2 1/2 for handgun. When Ive had a decent load for rifle match shooting, and tried to fine tune it by, say 2 1/2gr I could detect no difference in my group size. BTW, I have shot, and placed in chunk gun and BP ML bench matches. With the handgun I find a load that feels good that I can control and shoot it. If that is for score, on paper, I can use a lot less powder. For a walk-about where I might need a stout load it is another. I like 20gr. V of 2 or 3F in my .44 handguns, 15 in .36. for target/plinking. Fill the cylinder up in either with a RB and you have a man-killer.

[OLDPUPPYMAX]

I'd be willing to bet that Daniel Boone couldn't tell the difference between 72, 74 or 76 grains of powder, regardless of grain size. But part of the fun today is going through all of the permutations and combinations. Otherwise we'd all just own Glocks.

[AtlLaw]

Otherwise we'd all just own Glocks.

Now there's a boy with understandin!