weight and volume

[ferris bugler]

I just posted this on another site, but it seems like there is quite a bit of traffic here and I may get a better answer. Can you guys help me out on this?

Hey all. When I went to the range the other day I was trying to eliminate any type of inconsistencies. So I measured out 80 grains of T7 2F powder by volume, and since my only way to measure bp is in a quick loader and didn't seem too consistent I weighed it on a scale that I have for archery. At the range on a hot day 80 gr volume of T7 2F powder was 68 grains weight. Today, a little cooler and more humid, as I was preparing some loads to shoot during the season I seems like 68 grains by weight is more like 87 gr volume. Does this seem right? Is there an environmental change that would make this happen? What is the better way to choose the amount of powder I am going to use, or am I going nuts and they should consistently be the same. thanks in advance.

[Nobade]

I am not sure, since humidity doesn't factor in here very much, but it is quite possible that T7 changes in weight due to absorbed moisture. Another possibility is how the charges are thrown. Black powder can change dramatically in weight depending on how it is thrown into a container. Anyone who has used a drop tube to fill cartridge cases is familiar with this effect. This is why if you are shooting an accurate match rifle it is always good to pre-measure your charges and weigh them out on a scale to put in containers for use later. But for normal field use, charges thrown on the spot are plenty good enough, since a few grains difference in weight doesn't really make a noticeable difference in normal field situations.

-Nobade

[johnson1942]

i find most blackpowder subs. are spongy except real black powder and blackhorn 209 powder. pyrodox to me is the worst one for this. i dont know if they absorb humidity when they are spongy but it makes them hard to get accracy for me. they compress too easily. i honestly think if one could compress these difficult powders to get extreem accracy from the perfect same it would greatly improve their accracy. then you would have to contend with their crudring or soot. thats why i only have used real black or now blackhorn 209 powder. they have very firm grains of powder and are both very very accurate. their is no claeaning between shots with the 209 powder and real black is easy to clean between shots and consistantly accurate.

[ferris bugler]

Ok. Thanks for the advise. In the situation I'm in would one make a load using weight or volume? Thanks

[koger]

Volume!! BP or synthetic substitues are made to be used by volumetric measure, you can check them by weight, but if you weighed 90 grains, you might end up with 120 volume. I have seen more than one gun blown up by people weighing BP, instead of using measures.

[oldracer]

I load mine by volume since my mentor said he did it that way for 40 years. I periodically check the weight to see if a batch of my Goex FFG has changed but they stay very constant. I used some rigid copper tube, cut some pieces off and plugged one end to make static volume BP measures. I have a small bolt through it so the plug stays the same and use them for 70, 80, 90, 100, etc, etc.

[ferris bugler]

Volume!! BP or synthetic substitues are made to be used by volumetric measure, you can check them by weight, but if you weighed 90 grains, you might end up with 120 volume. I have seen more than one gun blown up by people weighing BP, instead of using measures.

Now I'm getting more confused. Is 68 weight grains of powder today the same as last week even though it takes up 7-10 more grains of volume?

[Beerd]

ferris,
try thinking of it the other way around.
if you always use the 80 grain VOLUME, today it might weigh 68 gr on a scale, next week it may weigh 64 gr or 72 gr, but it's still 80 on your powder measure.
..

[pietro]

.

IMHO, you're overthinking it.

The key for me, over the past 45 years, is consistancy in measuring the loads by volume - best accomplished by setting a BP adjustable powder measure to whatever load is the most accurate in the particular rifle.

The consistancy comes in when the loose powder is poured into the measure - which should be slightly overfilled, then struck off level with a square edge (over a pan, to catch/reuse the struck-off powder).

I pour my struck-off loads into a speedloader for convenience.


.

[ferris bugler]

Thanks. I'm pretty new to this and been having trouble getting consistent bullet flight. Finally thought I had it figured out and ran into this. Therefor I wanted to make sure I took out the right variables. Appreciate everyone taking some time to help me out.

[Omnivore]

What Pietro said.

Anyway; if you're weiging charges "at the range" as you put it, you'd be doing it outdoors, no? That won't work. Any air movements will throw off your scales.

Also; I've been weighing charges of smokeless, and all of a sudden my weights were off. Turns out the powder from one canister had run out and the measure started throwing powder of the same make and model of powder, but from a different canister. The densities from the two canisters of the exact same powder were slightly different.

With BP, don't worry about it. Just try to get consistent volume and concentrate on more important things like bullet fit, load selection, and and loading and shooting technique.

With all due respect I think you're asking the wrong question. You might want to start over, saying; "I have "a" firearm, with "b" barrel twist and "c" and "d" bore and groove diameters, shooting "e" charge of "f" powder using "g" projectile (and "h" patch) using "i" lube and it's producing groups of "j" inches at "k" distance. What should I try, to improve accuracy?" Or simply; "I have this specific gun. What would be some of more accurate loads for it?"

[fouronesix]

Yet another weight vs volume thread:veryconfu

I think you're problem with "consistent bullet flight" has very, very little to do with small charge to charge differences when using a volume measure for loading.

I'd look at other things that will affect how well a muzzleloader shoots …. and there bunch of them!

[Fly]

Guys BP does change weight as does how fast it burns from day to day. WHY? Humidity
plan & simple.The KNO-3 in it is a salt & that draws moister & also why it rust your guns.

Just stick to volume for every day shooting.There are reasons for weighting but that's for
another topic.
Fly

[Toymaker]

Several years ago there was an article in MuzzleBlasts magazine by the Bevel Brothers comparing weighed versus measured black powder charges. Anyone familiar with the Bevel Brothers knows they put out some great information with a good dose of humor which always seemed to make their point rememberable. The results of their "testing" gave a slight edge to weighed charges. I don't remember the reason why. But the difference wasn't significant and they would continue to use volume measures. I do use weighed charges for BPCR loads but the muzzle loaders are all charged by volume. I only use Goex.

[Geezer in NH]

You need a cheap to purchase brass powder measure I like the ones with the cutoff funnel on top less than $20 bucks. Forget weighing the charge.

[snowwolfe]

Always weigh for rifles. First measure out the correct volume then weigh it. From this point on if the load shoots good I weigh out charges at home on the scale and put them in those old 35mm plastic film canisters. Just easier for me to carry a zip lock bag of pre weighed charges to the range instead of a container of powder and measure.

[oldracer]

As we have seen here as with quite a few other posts, there is more than one way to do something. I would suggest trying using BOTH methods to see which works best for you, your rifle and most importantly......the accuracy of the final product. Only then should you make the decision on what to do!

[OverMax]

Without getting into too much theory. Measuring by Volume and by Scale both are two totally different weights. Volume measurer's sort of lie. Scale weight is actual.

Volume slide measure's were made to accommodate substitute powders measuring by (reduction) so to allow its use in B/P designed weapons.

Do to the Hodgdon companies saftey policy statement to reduced a T-777_ 2-FFg charge by 15% when used to achieve a 2-FFg Black Powders energy & pressure.
Volume measured 80-gr.charge X .15% =12__80 minus 12 =68.
So hunidity isn't adding weight to your T-777 when its Volume measured verses Scaled measured in this instance.