Adam, what is your scale set at? Fast, medium or slow for measuring changes in weight?
Turn Your FX-120i into a Prometheus
- Thread starter Sheldon N
- Start date
'Fast' response mode. Outputs 20 times a second.
How would you know if your scale began to drift. My pan weighs 150.52 and if that number is not in there before I set a charge on it, I know it's drifted
Ok guys i dont spend much time on this forum but adam asked me to give a quick review. I have had it a little over a week, and i payed full price for it (so you know its a honest review)
First off there are no issues calibrating when the trickler is plugged in. I have always been in the habit of calibrating everytime i use the scale, so that is not an issue.
When using the right lee scoop this thing is FAST!!!!!
Im easily getting less than 10 seconds per charge if you use the correct lee scoop to drop the weight. In the video below i think i was using a 2.2cc scoop which is about 30 grains of H4350. I did some tests with the 2.5 cc scoop (~34 grains) but found if i wasnt fast enough with the scoop then the trickler was already too far ahead and i would push the charge overweight. But if you are quick then a 7 second charge is easy.
I did my first full test of charging cases today and did 50 cases in 15 minutes, so around 18 seconds per. And that includes dumping the powder into each case. Im sure it will be even faster once i get a good routine. Out of the 50 charges I only had 1 that went "over", and it was .04 grains. Thats only 2 kernels.
Heres a quick video i made with the target charge being 40 grains.
feel free to ask any questions
First off there are no issues calibrating when the trickler is plugged in. I have always been in the habit of calibrating everytime i use the scale, so that is not an issue.
When using the right lee scoop this thing is FAST!!!!!
Im easily getting less than 10 seconds per charge if you use the correct lee scoop to drop the weight. In the video below i think i was using a 2.2cc scoop which is about 30 grains of H4350. I did some tests with the 2.5 cc scoop (~34 grains) but found if i wasnt fast enough with the scoop then the trickler was already too far ahead and i would push the charge overweight. But if you are quick then a 7 second charge is easy.
I did my first full test of charging cases today and did 50 cases in 15 minutes, so around 18 seconds per. And that includes dumping the powder into each case. Im sure it will be even faster once i get a good routine. Out of the 50 charges I only had 1 that went "over", and it was .04 grains. Thats only 2 kernels.
Heres a quick video i made with the target charge being 40 grains.
feel free to ask any questions
If using 10gr of powder per charge from the trickler, how often does it need to be replenished?
For god's sake Adam. Hurry up with the unit for the Sartorius Entris 64. Us Sartorius owners are down on our knees begin ya for one of these
Hey now...he's going to be busy building our units first.
iluvguns excellent video. This was an easy purchase.
Well the trickler holds around 450 grains of varget. Could probably add a little more in. So that's 45 rounds. But as I see it start to get low I just dump some in from my trusty solo cup
most of the time it does as its getting very close to the target weights. but with the size of the trickler opening it could have a few kernals that are clumped together. Dont see it being a huge issue
you could probably add an insert like the one sold here
http://www.scout.com/military/snipe...ding-px/13710820-chargemaster-reducing-insert
but it may slow down the trickler too much
Last edited:
I just went out to my bench and did some monkeying around with my Chargemaster which I have done before and I have come to the conclusion that no rotational trickler can trickle just one kernel consistently. Can't be done. If we are looking for one kernel resolution which most of the Sartorius and FX-120i balances can detect then we are going to have to come up with a different trickler either like the very expensive one on the Promethius or something like the Omega II which has it's own set of problems which can hopefully be solved.
yes you can do that
That is just slick!
Do you have a second metal powder pan of the same type? You could use a file to take a tiny bit off one so that they were the exact same weight, which would eliminate the need to rezero the scale. Then you could swap pans and while one was filling you would dump a charge in the funnel/case, toss in a scoop of powder with the Lee scoop, then swap pans again and repeat the process.
It would almost double your speed of case loading.... your hands would always be busy, the trickler would always be busy, and you'd never be watching the trickler work.
Here are some statistics around trying to measure "within 1 kernel".
For 308, many powders produce roughly 50 fps per grain. 1 kernel ~= 1 milligram ~= 1 fps. The perfect example is 2700 fps in 30 inch barrel with 185 Juggernaut. That takes 2.700 grams of H4895. Magic!
First understand random error in general. Suppose you drop one extra kernel in. That charge is now 1 fps hotter than it was supposed to be. But 50% of the time, that charge was destined to produce a lower velocity due to other factors, and actually helps you. When you have many sources of error that combine to produce a single output, the result is normally distributed (central limit theorem). Therefore, you can use SD to quantify and account for the effect of each source of error. 1 more kernel does not mean 1 fps of error; it depends on all the other errors as well.
95% of normally distributed data fits within +/- 2 SD of the mean. So "within 1 kernel 95% of the time" means an "error SD of 0.25 kernels".
Now suppose your SD goal is 5 fps. That would be a great load, capable of holding (based on velocity ballistics for a 185 Juggernaut) 0.6 moa at 1000yd.
Assuming you had absolutely no error whatsoever from powder measurement, your SD would be 5.000 fps.
Now if you add an 0.25 fps error from measuring to 1 kernel, your SD will be sqrt(5^2+0.25^2) = 5.006.
If you measure to within 3 kernels 95% of the time, your SD will be 5.056. That's 1%.
My system will get you within 3 kernels 95% of the time. That is +/- 1 kernel ES, and error SD of 0.75. I load in milligrams, and accept anything 1 mg above or 1 below the target. This way I get 15 second case charging rate and I know my effect on velocity is less than 1%.
I also let the scale re-zero itself each time, but I wouldn't criticize anyone who doubled his loading speed at the cost of 1 kernel worth of drift error.
As an aside, I also weigh primers very carefully with this scale, because 1 milligram of primer weight has about 30% more effect on your velocity than 1 milligram of powder. Based on my own testing. And the match primers in my house have over 10 milligrams of weight difference.
... even worse, you used *STATISTICS* 
... in an Internet gun forum 
Upgrades & Donations
This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.