POWDER THROWS ~ Let’s talk some…

How many hundreds or thousands of times have we looked into the powder filled case prior to setting and seating the projectile and had that uneasy feeling that…’that powder level doesn’t look right’? How many times have you listened to that uneasy feeling and stopped and weighed every charge that made us question the powder level in the case?

If we used only one powder and one powder throw we would get accustomed to how it handles that powder, how much it will vary in tenths of a grain with differing metered amounts of powder…we could get very familiar with the performance of the two in concert, but this is not the case today. A new reloader may be using 2 or 3 powders in starting off, but the seasoned reloader who loads for every platform in his safe may use as many as a dozen different types of powder and may have a half dozen throws or more that they use.

How do they determine which throw they will use with what powder? For many years I used the Hornady powder measure that came with my Hornady LnL progressive press and it just never occurred to me to pull that measure and experiment with another. By then I had developed pretty good judgement of what powders I can use in that measure and unfortunately had to quit using a couple of powders that I really liked because they were miserable to try to meter with accuracy…they would vary by as much as 3 or 4 tenths of a grain. How the heck can I justify using one of those powders when I’m loading a caliber to within 2 tenths of maximum load recommendation? The answer is that I can’t…I don’t like to hear ‘I can’t’, there must be a way.

This lead me to the idea of using a different powder measure on my LnL progressive and that ended up being several powder measures got tried. With each measure I found that they too had powders that they could not meter efficiently. Why? What’s the reason for this? Well…unfortunately…the answer is to be found in some physics book somewhere, but the fact that it is physics lets us make some observations and draw some conclusions about the abilities of these throws.

This gave me the idea of investigating these mysteries in a series of videos where I would try several measures with several powders, record their performance and try to develop some kind of system to know the ‘why’s’ and then predict the best throw for whichever powder I want to use. I thought I’d go through the various types of powders including flake, ball and flattened ball and stick or extruded powders, but since then have ruled out the extruded powders because to meter them over and over again means to cut their grains many hundreds of times and would change the performance of the powder to the point where I would not trust what it might do. Extruded powders are made this way to control the burn rate by the coatings they use, the length and number of perforations within the stick itself and its size diameter. Therefore I will not sacrifice several pounds of stick powder for this experiment…that doesn’t mean we can’t get to the bottom of which throw will do best for sticks but we’ll have to do it another way.

Let’s us get on the same page, the same mindset before you start viewing these videos. This investigation starts off with me thinking solely ‘physics’…our powder throws have two general size metering holes in their metering drums, a smaller diameter hole for pistol with a limited range of volumetric metering in grains of weight and there’s a larger diameter metering hole for rifles with it also having a limited volumetric range. This is true for the old school powder throws that have been around since we all were pups, but today there are new throws, cheap throws, plastic throws and their metering holes pretty much follow the same small and larger diameter metering holes for the volume expected of that particular measure. Some of these new throws handle the powders amazingly well due to the way they engineer their metering within the throw. Therefore this is not a series of videos about which manufacturer’s measure does the best job, instead it is about looking at the physics of metering odd shapes in small holes and doing it consistently. It is about trying to understand why powders are harder than others to meter and…can we do anything in the future to predict the success we will have trying to accurately and consistently meter our powders?

Here are my videos thus far…

POWDER THROWS ~ introduction ~ Let’s talk some…

 

VOLUMETRIC POWDER THROWS ~ IMR 700X ~ The Mechanics of METERING

 

VOLUMETRIC POWDER THROWS ~ Bullseye ~ The Mechanics of METERING

 

POWDER THROW ~ test 3 ~ More Pistol Powders

 
Anyone who wants to get an idea of what some new to them powder looks like before they buy to try, there’s a web site where you can see pictures of all the various powders and see their sizes of flake, ball and extruded shapes…

http://www.ilrc.ucf.edu/powders/sample_detail.php?powder_id=385

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