how to measure BP substitute powders

[Kart29]

Okay, I got my Huntsman barrel yesterday.  I also picked up a pound of 777 FFg powder.  I know I want to try powder charges ranging from 90 to 120 grains.  I have an adjustable brass powder measure (volume) of unknown quantity, a Lee powder scale (weight), and a set of Lee powder dippers measuring out in CC's.  I have a VMD coversion factor in my Lee Modern Reloading manual for converting volume of FFg black powder to weight (or vice versa).

So, how do I use these tools to measure out 777?

Questions:

1.  Is the term "grain" used as both a measure of weight and a measure of volume?  I know in smokeless powder, a "grain" is a measure of weight.  But 777 and Pyrodex always talk about grains powder by volume.  Are we really measuring say 100 grains of volume?  Or are we measuring the volume of powder that would produce a weight of 100 grains if the powder used were true black powder?


2.  How is black powder measured?  I know we meter and load using a volume measure.  But are black powder loads still described in terms of weight?   That is, when we mention a load of 100 grains of black powder, does that mean 100 grains of weight even though we acheive that using a volumetric metering device?

3.  Do black powder substitutes have the same weight per volume that black powder does?  I could fill my brass powder measure, dump it into my Lee powder scale and see how much it weighs.  But, if the density of 777 is dfferent than that of bp, the volumetric measure that dumps out 90 grains weight of bp may dump out the same volume of 777 that may weigh more or less than bp.

4.  If the term "grains" can be used to describe to volume as well as weight, is there a way to convert volumetric grains to cubic centimeters?

I guess what it boils down to is this - I have a way to measure 777 in weight (powder scale), and a way to measure 777 by cc (Lee powder dippers).  How do I use this to produce the charge the powder manufacturer describes as "100 grains by volume"?   And then, how do I determine the amount of powder thrown by my brass powder measure.

I hope I haven't made this too complicated to try and answer.

Thanks folks!

[Busta]

Okay, I got my Huntsman barrel yesterday.  I also picked up a pound of 777 FFg powder.  I know I want to try powder charges ranging from 90 to 120 grains.  I have an adjustable brass powder measure (volume) of unknown quantity, a Lee powder scale (weight), and a set of Lee powder dippers measuring out in CC's.  I have a VMD coversion factor in my Lee Modern Reloading manual for converting volume of FFg black powder to weight (or vice versa).

So, how do I use these tools to measure out 777?

Questions:

1.  Is the term "grain" used as both a measure of weight and a measure of volume?  I know in smokeless powder, a "grain" is a measure of weight.  But 777 and Pyrodex always talk about grains powder by volume.  Are we really measuring say 100 grains of volume?  Or are we measuring the volume of powder that would produce a weight of 100 grains if the powder used were true black powder?

Answer: Your right, smokeless is grains by weight, the Black Powder (BP) and Black Powder Substitutes (BPS) are grains by volume. Since TRUE Black Powder is the STANDARD, 100 grains by weight of Black Powder also is 100 grains by VOLUME. Now Black Powder Substitutes are measured to that standard by VOLUME and NOT WEIGHT. The BPS are lighter that BP, and produce higher velocities with the same volumetric measure. 100 grains of Pyrodex by VOLUME is very close to 100 grains by VOLUME of Black Powder and is considered it's equivelant although it only weighs about 85% of BP.

 Now comes 777 Powder, this is the exception to the above rule, so pay close attention to this part. 777 LOOSE Powder is more energetic than BP and other BPS. 777 FFG and 777 FFFG are also measured by VOLUME, but this is NOT the same as other BPS. 85 grains of 777 FFG or 80 grains of 777 FFFG  by VOLUME is equivelant to 100 grains by VOLUME of Black Powder and other Black Powder Substitutes. REMEMBER THIS!

Now 777 Pellets on the other hand are equivelant to Pyrodex Pellets and Black Powder and Black Powder Substitutes by VOLUME. A 50 grain Pellet is equivelant to 50 grains of Black Powder or Black Powder Substitutes by VOLUME. REMEMBER THIS ALSO!  A two 50 grain pellet load of 777 (100 grain pellet charge) is equivelant to a two 50 grain pellet load of Pyrodex (100 grain pellet charge) or 100 grains of LOOSE Black powder or Black Powder Substitute with the exception of 777 loose powder.

85 grains 777 FFG or 80 grains 777 FFFG by VOLUME are equal to two 50 grain 777 Pellets (100 grain pellet charge)

I know this is confusing at first, but if you are shooting 777 FFG, just remember 85 grains 777 FFG by VOLUME is equivelant to 100 grains of BP or any other BPS, whether it be loose or pellets.


2.  How is black powder measured?  I know we meter and load using a volume measure.  But are black powder loads still described in terms of weight?   That is, when we mention a load of 100 grains of black powder, does that mean 100 grains of weight even though we acheive that using a volumetric metering device?

Answer: Remember, Black Powder is the STANDARD. 100 grains by WEIGHT of Black Powder is also 100 grains by VOLUME of Black Powder.

3.  Do black powder substitutes have the same weight per volume that black powder does?  I could fill my brass powder measure, dump it into my Lee powder scale and see how much it weighs.  But, if the density of 777 is dfferent than that of bp, the volumetric measure that dumps out 90 grains weight of bp may dump out the same volume of 777 that may weigh more or less than bp.

Answer: No, Black Powder Subs are not the same weight as Black Powder. 777 is WAY lighter than Black Powder, approximately 25% LIGHTER, so don't ever use weight to measure. The only EXCEPTION would be to WEIGH out your VOLUME measured load, but I would not suggest that until you get a little more experience under your belt. The weight of powders can vary from batch to batch, temperature and humidity.

4.  If the term "grains" can be used to describe to volume as well as weight, is there a way to convert volumetric grains to cubic centimeters?

I guess what it boils down to is this - I have a way to measure 777 in weight (powder scale), and a way to measure 777 by cc (Lee powder dippers).  How do I use this to produce the charge the powder manufacturer describes as "100 grains by volume"?   And then, how do I determine the amount of powder thrown by my brass powder measure.

Answer: Forget the dippers, unless you have a BIG dipper to throw charges that you will be using, you will be wasting your time. Take your brass powder measure in the fully collapsed position it would be 50 grains by VOLUME for a rifle powder measure. Each graduation (groove) as you open it up will add 10 grains by VOLUME to your charge, with 120 grains by VOLUME being the maximum charge. As you open it up, the first click will be 60, second 70, third 80, fourth 90, fifth 100, sixth 110, seventh and last groove will be 120 grains by Volume.

I hope I haven't made this too complicated to try and answer.

Thanks folks!

I hope I haven't confused you, but if you are confused, ASK for clarification BEFORE you go shoot your rifle. BE SAFE and ask questions. Lots of people here willing to help you get started down the right path.

[Kart29]

Great BUSTA!  Thanks!  I understand.

When we say 80 grains of BPS, we mean the volume of BPS where the same volume of black powder would weigh 80 grains.  Got it.

However, I'm not sure I agree with you about needing to reduce the volume of granular 777.  The Hodgden website says: 

"Triple Seven is a high energy product designed to provide the muzzleloading hunter with higher velocities when used in the same VOLUME as black powder. To duplicate a black powder load velocity using Triple Seven, you must decrease the powder charge by 15%."

  Note that it says, we will get high velocities using the SAME volume.  Reducing the powder charge by a percentage is required when trying to duplicate BP load velocities.

One additional question, though.  How do you know my brass powder measure is 50 - 120 grains at 10 grain increments?  I can't remember who made it, T/C or CVA or somebody else.  I know it is the rifle size measure and not the pistol size measure.  Is there some sort of convention for powder measure manufacturers?

[Busta]

Great BUSTA!  Thanks!  I understand.

When we say 80 grains of BPS, we mean the volume of BPS where the same volume of black powder would weigh 80 grains.  Got it.

However, I'm not sure I agree with you about needing to reduce the volume of granular 777.  The Hodgden website says: 

"Triple Seven is a high energy product designed to provide the muzzleloading hunter with higher velocities when used in the same VOLUME as black powder. To duplicate a black powder load velocity using Triple Seven, you must decrease the powder charge by 15%."

  Note that it says, we will get high velocities using the SAME volume.  Reducing the powder charge by a percentage is required when trying to duplicate BP load velocities.

One additional question, though.  How do you know my brass powder measure is 50 - 120 grains at 10 grain increments?  I can't remember who made it, T/C or CVA or somebody else.  I know it is the rifle size measure and not the pistol size measure.  Is there some sort of convention for powder measure manufacturers?

When I said you need to reduce the loads for 777, what I meant was to reach the equivelant load of the other powders. That is the beauty of 777, you can burn the same amount of powder by volume in the same space with higher velocities, or use less powder to achive equal velocities. Just remember Hodgdons website also says no more than two pellets, but most of the manufacturers of the rifles are telling you you can use three. One thing I do know, is don't use any more than 120 grains of loose 777 in a rifle that is considered a "Magnum", capable of shooting 3 pellets (150 gr pellet load) by the manufacturer.

The key is, read your owners manual, follow the advice in it as far as maximum loads and you should be fine.

Your brass powder measure should have have had instructions with it when you bought it new. If it is a T/C rifle (not pistol) measure, it will start at 50 fully closed and go to 120 in 10 grain increments by volume. I am sure any of the others are the same, but to be sure you could purchase one of the clear view measures that have the numbers on the side. You could also ask someone experienced in muzzleloading, could even cross measure from there measure to yours to double check it. If you are not sure, find out first.

[PA-Joe]

Does the stem of your power measure have a scale on it. That should be a BP scale and you should be ok to use it.

[quickdtoo]

FWIW, all of my brass powder measures have 5gr marks between the 10gr markings, have 10gr thru 120gr or 150gr markings. I wouldn't want it any other way, most of my Goex and T7 loads have been the most accurate at the 5gr increments, making 10gr changes can skip the "sweet" load.

Tim

[Busta]

Kart29,

The measure I am talking about is the second one down No. 7040, it is one of the more popular ones that have been around for several years. The newer measures have actual numbers and are much better for tweaking your loads. Check these out, yours might just be there. If it is another brand, you can look on their sites. Just make sure before you use it, for safety sake. Better yet, buy a new one such as the U-View No. 7222, second from the bottom.

[Kart29]

I found this link on the web:

http://www.curtrich.com/BPConversionSheet.htm

According this site, 100 grain volume of 777 FFg should weigh about 73.3 grains in a powder scale.  I know this isn't gospel because density of a given powder will vary from lot to lot.  But, if the powder weight is between 65 to 80 grains, it will provide a confirmation that my volume measure is indeed metering 50-120 grains in 10 grain increments as I think it is.  On the contrary, if I set the volume measure to what I think is 100 grains volume and that volume of 777 weighs out at say 35 grains, or 110 grains on my scale....then I'll have reason to believe my brass volume measure isn't what I think it is.

Busta, I assume you are looking at this page:

http://www.tcarms.com/tc_html/accessrs_powder.htm

My powder measure looks exactly like #7040.  Also, I remember when I bought it that it came in a blister package that had instructions for two different powder measures - a rifle measure (larger) and a pistol measure (smaller).  I remember this because when I purchased the measure, the price tag was applied over the text that described the rifle measure, leaving only the specifications of the pistol measure visible on the package.  So, I started out using the rifle measure and adjusting it according to the pistol measure specifications as visible on the package.  I thought I was metering out 100 grains volume when in reality I was metering out 200+ grains of Pyrodex RS.  I was shooting this in a CVA Kentucky long rifle I built from a kit.  Good thing it was Pyrodex!  If it had been real black powder that charge may have damaged my gun and/or my face.  As it was, that charge just blew alot of smoke and fire out the barrel.  That was 18 years ago.

Even though my powder measure is shaped exactly like #7040, I'm thinking it is actually sized like the magnum measure #7102.  I took my measure in to the store a few days ago and held it up to a measure for sale in the store.  Mine looked almost identically sized to the measure for sale in the store, and the measure for sale in the store was shaped like what T/C calls their magnum measure now.

Anyway, having some guideline as to the expected weight for a given volume of 777 I should be able to figure out how my measure is calibrated.

As soon as I get it figured out the first thing I'm going to do is engrave the brass barrel with the measure specifications so I won't have to go through this again if I throw the measure in a drawer and forget about it for another 15 years.

Thanks, all of you, for your help.

[Busta]

Kart,

I'm sorry, I forgot to add the link. Yes that is the page I was talking about.

http://www.tcarms.com/tc_html/accessrs_powder.htm