Powder measure

[bud in pa]

Question for those of you who use a fixed home made measure. How do you determine how large to make the cavity to hold your charge? I weigh my charge on my reloading scale and the I usually use a 3/8" bit to make the cavity, I will eyeball the depth and add the charge, then either I will deepen the cavity or trim the measure until the charge is flush with the top.

 

[coloradoclyde]

Weight is irrelevant....

First I find my accurate load using a volumetric measure....Then I make my measure by slowly enlarging, lengthening , or shortening depending on the type of measure I am making ...until the two volumes match.

You could do the same by weight....but you must find your accurate load first.....And realize that substitute powders weight differently by volume.

Remember a powder "measure" is a unit of volume not weight.

 

[Zonie]

IMO, the only time weight is irrelevant is if we are talking about shooting a solid projectile accurately and even then, the measure needs to throw the amount of black powder by the weight that made for the good accuracy for it to have any meaning other people can relate to.

As this is the smoothbore section, I'll assume bud in pa was asking about a particular powder load like say, a 2 1/2 or 3 dram, or maybe a 75 or 90 grain load.

If that is the case, as long as he's weighing real black powder, I'd say he's on the right track.

I agree with you about substitute powders.

They all weigh less per cubic cc or cubic inch than real black powder so weighing any of those won't work to make the kind of measure he needs.

 

[coloradoclyde]

Opps! I forgot this was the smoothbore forum....Yes I was centered on rifles..

Thanks for the critique.... :thumbsup:

 

[tenngun]

I drill a deeper then needed hole, then run out a measur os salt to the volume I want then dump it in the hole, mark and cut off.

 

[BrownBear]

I drill a deeper then needed hole, then run out a measur os salt to the volume I want then dump it in the hole, mark and cut off.

Same here. I'll add that I save the exterior finish work until I have the depth right. No sense getting all finished up with the trim-to-length method you and I use. Drill and drill deeper would be the only option if the exterior was already finished.

 

[rodwha]

I must confess that I'm at a loss here as "grains" is a measurement of weight and not volume.

 

[George]

If the measure comes out larger than you want, or if you want to reduce the size temporarily, light a candle and drip some wax in the bottom to make it right. Too much wax? Drill a tad out by hand. I have measures several years old which have been waxed, and the volume stays correct.

I also frequently mark a fixed antler or cane measure inside with a line for another weight. Proper size measure for shot with a proper, lesser weight for powder marked inside. Works.

Spence

 

[coloradoclyde]

I must confess that I'm at a loss here as "grains" is a measurement of weight and not volume.

And a pint weighs a pound....

Bushels are also a volumetric measure of weight that varies depending on what's in the bushel....

Confused yet?

 

[Feltwad]

Question for those of you who use a fixed home made measure. How do you determine how large to make the cavity to hold your charge? I weigh my charge on my reloading scale and the I usually use a 3/8" bit to make the cavity, I will eyeball the depth and add the charge, then either I will deepen the cavity or trim the measure until the charge is flush with the top.

Buy yourself a powder flask that throws a measure from 2.1/2 drms to 3.1/2 drms powder select your load and pour into a small powder thimble then into the barrel ,this will give you the proper load every time . To pour loose powder into a measure can give you a different loads .
Feltwad

 

[azmntman]

whats the difference? powder from the flask is loose as well?

 

[azmntman]

I must confess that I'm at a loss here as "grains" is a measurement of weight and not volume.

A cup of lead and a cup of flour are the same volume but weigh a bit different.

So BP is lead, Pyrodex is flour, T7 is cream of wheat, Black MZ is corn meal, shockeys gold is dirt. Got it?

 

[Feltwad]

whats the difference? powder from the flask is loose as well?

Shooters that use a powder flask know the load is measured from the adjustable measure on the flask,then it is poured into small container such has a thimble measure then into the barrel. When powder is poured straight from a horn into a home made measure the load can differ a lot .
Feltwad

 

[Feltwad]

Enclosed two images of what I use
Feltwad

Powder flask plus measure for pouring


Required measure on the flask

 

[Grenadier1758]

Question for those of you who use a fixed home made measure. How do you determine how large to make the cavity to hold your charge? I weigh my charge on my reloading scale and the I usually use a 3/8" bit to make the cavity, I will eyeball the depth and add the charge, then either I will deepen the cavity or trim the measure until the charge is flush with the top.

It seems as if you want to make your own powder measure.

An old rule of thumb that i have used is that a drill bit of 29/64" diameter will make a hole that will hold 10 grains of powder for every 1/4" of depth. This is for a fairly dense black powder so you may have to drill a bit deeper to adjust for you final calculation.

 

[BrownBear]

If the measure comes out larger than you want, or if you want to reduce the size temporarily, light a candle and drip some wax in the bottom to make it right. Too much wax? Drill a tad out by hand. I have measures several years old which have been waxed, and the volume stays correct.

I also frequently mark a fixed antler or cane measure inside with a line for another weight. Proper size measure for shot with a proper, lesser weight for powder marked inside. Works.

Spence

Those are good suggestions, but I mostly just shorten the measure to adjust it, the big reason I do my drilling before shaping the horn. This simple measure (30 grains) from a horn tip is an example. I'll get around to fancying up the exterior "one of these days" but it's perfectly serviceable now.

The horn diameter was quite a bit larger when I drilled and shortened, but I re-tapered the exterior. Nice thing about drilling and adjusting first before shaping, you can adjust for a hole that's a little off-center. I've been known to do that on many an occasion! :rotf:

 

[nwtradegun]

powder charge is by volume not wieght.

 

[Billnpatti]

powder charge is by volume not wieght.

Actually, powder is measured in "volume equivalents" not purely by volume. If we measured by volume alone, we would speak of loading a charge of 1/2 cubic inch of powder or 10 milliliters of powder. Rather, we speak of loading so many grains of powder and use a measure that gives us a volume equivalent to that many grains. Does this volume actually give us that many grains of powder? Only if it is first calibrated for the exact powder that we are using. Different brands and different granulations have different bulk densities and that measure will throw a different number of actual grains of powder depending on the bulk density of the powder. So, yes we do measure by volume but it is a volume equivalent (albeit an approximation) to a certain weight of powder. We load by weight but we measure that weight by its volume equivalent.

Confusing? Only the explanation, in actual practice it is pretty simple.

 

[jrmflintlock]

I think your confusion stems from cartridge reloading where the given "grains" of powder for a cartridge is a measure of weight. As Billnpatti stated in muzzle loading it's a weight equivalent. An as others have said you can go through the process of figuring it out, but the simplest solution is to buy a commercial black powder measure, determine the load your firearm likes then make yourself a fixed powder measure out of your choice of material.

I understand your desire to not purchase a measure you will rarely use but there is really no way around it. If you really don't want to buy one maybe someone can lend you one.

Hope this helps! Good luck!

 

[Grenadier1758]

The question I should have asked is this, "How many grains of what powder are you wanting to measure?" Once I know how many grains (volume) of black powder you want to make the measure for and what size (3/8") drill, then I can make a suggestion for the depth you should use.

For example: Using the 3/8" drill, a 1" deep hole wil measure 27.5 grains.