Chargemaster and a RCBS powder trickler.
Powder Handling
- Thread starter Richard Coody
- Start date
The problem with making accurate loads with an inexpensive scale is that inexpensive scales are not very good. Us poor folks who think they need precision greater than 0.1gr typically use a Gem Pro. That's what I use. It does NOT work as you would hope and it requires quite a bit of user technique to find success. For one thing, it fights back when you try to trickle a charge. It simply doesn't respond and then suddenly jumps up to reveal an overshoot.
It also tends to wander and lose it's zero if you fool around too long when adding and subtracting powder from the pan. When you finally dump the powder charge and replace the pan, you discover that the zero has drifted a few tenths of a grain. When you hit the tare button and reweigh the last charge, you'll often discover an error.
However, it doesn't take long to learn how much a kernel of Varget or other similar short stick powder weighs; close to .02gr. So if I can get my Chargemaster to make a load which weighs within about .04gr of my target when I transfer it to my Gem Pro, then I can simply add one kernal per .02 gr and call it good. Outside that one or two kernel range, I add or subtract a few kernels and re-weigh the sample. That involves lifting the pan, shaking it to center the charge (yes, a charge not centered in the pan will unfortunately produce an error), and then reweighing the charge. I may make one more correction but if that doesn't hit the mark, I start over. I dump the powder into the cartridge temporarily, re-tare the pan, and dump the powder back on the Gem Pro to confirm that I'm at the target weight or within a kernel or two.
The sad truth is that you can't fiddle around adding and subtracting powder to the Gem Pro without it losing it's tiny mind. Then you gotta' rezero it and start again.
Yes, it's a PITA but it's necessary to get within a kernel or two if you don't want to spend all day weighing powder using a Gem Pro. The Chargemaster will do that for me most times and I can quickly and accurately hit the target weight within .02gr. Unfortunately, I can't get that close with a powder dipper or a simple mechanical measuring device.
All this is less than ideal, but it's the price you pay for a piece of gear which isn't actually all that cheap, but it's way down the food chain from more suitable scales which cost way more than I'm willing to spend.
It also tends to wander and lose it's zero if you fool around too long when adding and subtracting powder from the pan. When you finally dump the powder charge and replace the pan, you discover that the zero has drifted a few tenths of a grain. When you hit the tare button and reweigh the last charge, you'll often discover an error.
However, it doesn't take long to learn how much a kernel of Varget or other similar short stick powder weighs; close to .02gr. So if I can get my Chargemaster to make a load which weighs within about .04gr of my target when I transfer it to my Gem Pro, then I can simply add one kernal per .02 gr and call it good. Outside that one or two kernel range, I add or subtract a few kernels and re-weigh the sample. That involves lifting the pan, shaking it to center the charge (yes, a charge not centered in the pan will unfortunately produce an error), and then reweighing the charge. I may make one more correction but if that doesn't hit the mark, I start over. I dump the powder into the cartridge temporarily, re-tare the pan, and dump the powder back on the Gem Pro to confirm that I'm at the target weight or within a kernel or two.
The sad truth is that you can't fiddle around adding and subtracting powder to the Gem Pro without it losing it's tiny mind. Then you gotta' rezero it and start again.
Yes, it's a PITA but it's necessary to get within a kernel or two if you don't want to spend all day weighing powder using a Gem Pro. The Chargemaster will do that for me most times and I can quickly and accurately hit the target weight within .02gr. Unfortunately, I can't get that close with a powder dipper or a simple mechanical measuring device.
All this is less than ideal, but it's the price you pay for a piece of gear which isn't actually all that cheap, but it's way down the food chain from more suitable scales which cost way more than I'm willing to spend.
Last edited:
fwiw,
Harrell's Premium to Sartorius to Dandy Trickler. Waiting for the product improved auto trickler...
Regards, Matt.
Harrell's Premium to Sartorius to Dandy Trickler. Waiting for the product improved auto trickler...
Regards, Matt.
I saw what Adam did and made my own for about 60 bucks, all parts from amazon. I added some features on my code that allow me to custom configure my unit using SD card, things like trickle speed tweaks, scale communication speed and data logging. It records uptime of the unit along with each charge created how long it took to create that charge and displays it in two ways. My unit is network aware and is a webserver where you can see each charge logged. You can download the logged data for analysis in MS excel. I wanted the capability of not having to create a charge and place it on the scale although it works that way too, I added a keypad for just setting your weight. I also wanted to see what was going on inside my machine so I added the LCD display, and yeah a little screen saver for it. Screen saver customizable and wakes up on keypad press. Some future plans are possible bluetooth so I can maybe do away with the keypad and use my phone but oh well the keypad works fine for now.
I haven't created an auto-charger but that shouldn't be to hard with another stepper motor and a couple pins off my arduino and motor driver.
Right now I use my charge master for initial load, and use the arduino trickler to bring it up to precision.
I haven't created an auto-charger but that shouldn't be to hard with another stepper motor and a couple pins off my arduino and motor driver.
Right now I use my charge master for initial load, and use the arduino trickler to bring it up to precision.
redding BR-30 or BR, RCBS 10-10, RCBS 304
I'll add an option to your list.... powder thrower and kernel counting with a GemPro. Fast and accurate. More details and a video here...
http://forum.accurateshooter.com/threads/speed-up-your-powder-weighing-a-different-approach.3910201/
Just wanted to share an update on my trickler from above.
Doing two methods of automated powder trickling:
Method 1 using my phone app to plug in the weight for trickling to the A&D 120i/Sartorius
Method 2 using Amazon Alexa voice control
I have an auto charge dropper as well but its on the Sartorius
Now thinking of creating presets for when I walk in the room and just tell Alexa to start my favorites like a spotify play list lol. Only limited by my shooting skill and imagination
Doing two methods of automated powder trickling:
Method 1 using my phone app to plug in the weight for trickling to the A&D 120i/Sartorius
Method 2 using Amazon Alexa voice control
I have an auto charge dropper as well but its on the Sartorius
Now thinking of creating presets for when I walk in the room and just tell Alexa to start my favorites like a spotify play list lol. Only limited by my shooting skill and imagination
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