Going digital ...

[jski]

Got tired of the laborious efforts required weighing using the ol' pan scales. So, after much online research, I bought a GemPro 250 digital scale to make my life simpler ... or so I thought. The GemPro out-of-the-box experience was what I had hope for ... simple. I plugged it in, easily calibrated the scale, and was up and running.

Weighed some bullets and got the values I expected. Weighed a small weight of precisely known value ... dead on. All was good.

Then I started weighing powder charges thrown by my RCBS powder dispenser. Adjusted the settings to where I thought I needed to be, locked down the dispenser, and did something I had never done before ... I started randomly weighing charges during my reloading.

To my chagrin, they differed by as much as .3 grains. I put the precise weight back on the scale ... dead on. I re-weighed some of the aforementioned bullets ... good.

So is it the GemPro or my RCBS powder dispenser?

 

[AZAndy]

What powder is it? I've had some variances, though not .3, with Unique in a Lee Autodrum. Titegroup and W231 don't give me as much trouble.

 

[stringnut]

Depends on the powder and the amounts. Some powders just meter better than others. Stick powders, especially, can vary a lot. Three tenths of a grain would be a large change in tiny cartridges and insignificant in larger ones. If you are loading 6 grains .3 is 5% which can cause issues. 50 grains the .3 is only.6%.

 

[jmorris]

My charge masters automatically establish zeros by themselves. That's one "feature" I would like to turn off. If things change I prefer to be the one to change them or at least know that there is a change happening.



The beam scale/contraption at the end of that video is used like this.



It doesn't auto zero, has a higher resolution for greater repeatability and is cheaper. Just not as neat looking.

 

[cfullgraf]

Adjusted the settings to where I thought I needed to be, locked down the dispenser, and did something I had never done before ... I started randomly weighing charges during my reloading.

Well, then you do not have a history of the capability of your powder measure to judge against.

To my chagrin, they differed by as much as .3 grains. I put the precise weight back on the scale ... dead on. I re-weighed some of the aforementioned bullets ... good.

I'd have to say its the powder measure.

That's not to say that the powder measure is not capable. With powders with a reputation of being difficult to use in a powder measure, it takes a bit more care to get uniform throws from the powder measure.

 

[Load Master]

Yeah, not sure which RCBS you have, as already pointed out by jmorris the RCBS will self zero, even their newest model pictured below. The balance beam scale still is my go-to for true accurate and low standard deviation round to round. I have a GemPro 250 and it is one of the best digital scales of many I have owned, but, I will never give up my balance beam.

 

[higgite]

I'm guessing that OP's RCBS powder dispenser is a Uniflow, not a Chargemaster, since he said he has gone digital and now uses a GemPro instead of a pan scale. Since there is no history of random measuring with the pan scale, the test to see if the problem is the powder measure or the new scale is to weigh random charges with the GemPro AND the pan scale. I'm betting on the powder measure being inconsistent with whatever particular powder the OP is using. For some reason, I get up to a +/-.2gr spread with Universal in my Uniflow, but always less than a +/-.1gr spread with W231.

 

[jski]

The powder was Hodgdon's H110. The powder dispenser is the RCBS Uniflow:

 

[jmorris]

I would clean out your measure and inspect. H110/296 will meter better than .3gn out of measures far inferior to any of the uniflow measures.

 

[MEHavey]

It's the Measure giving you the disparity, not the Scale (honest )
And barring static cling, H110/296 should measure like water.

OOC, what throw technique are you using?

 

[jski]

I'm loading for .30 Carbine, .357 Mag, .45 Colt most of the time. The .30 Carbine and .357 Mag aren't particularly sensitive to that kind of variation. But the .45 Colt for my S&W Mountain Gun, could be. I haven't tried this experiment with Hodgdon's Titegroup, which I use for my .45 Colt rounds.

 

[MEHavey]

OOC, what throw technique are you using?

 

[higgite]

Who is OOC?

 

[jski]

what throw technique are you using?

Lever up. Lever down.

 

[Demi-human]

Very much the dispenser.

 

[Lokichoki]

4227 meters well in my measure for 30carb, as for the variance in weight that doesn't sound odd to me with a powder measure there's a reason we have tricklers I always go under as low as I can without wasting time and trickle in till spot on, if you want to load fast you have to either accept the variance and load accordingly or do this method or buy a auto dispenser one, I used a Hornady scale for a year that went up and down .1 gr I'd have to pull the pan and adjust to wether it was -156.5 or up or down for my charge. Assuming your scale weighs fine I'd try a powder that has been reviewed as being good in a measure/meter also try tapping lightly on the up and pour stroke to settle and remove any extra granuals that might be stuck in the neck

 

[MEHavey]

Lever up. Lever down

try the following:

- Pushing the handle *in* to positively get same barrel position
- Up sharply ("snap")
- Down sharply ("snap")
- Double sharp "Tap-Tap" at the bottom

Try it... tell us what (if anything) you get different in consistency w/ the H110

 

[TheDomFather]

My charge masters automatically establish zeros by themselves. That's one "feature" I would like to turn off. If things change I prefer to be the one to change them or at least know that there is a change happening.



The beam scale/contraption at the end of that video is used like this.



It doesn't auto zero, has a higher resolution for greater repeatability and is cheaper. Just not as neat looking.

My hornady auto Zeros as well. Not sure I love that feature either. I have an RCBS beam scale I use to verify every few charges and so far it seems to be dead on

 

[TheDomFather]

The powder was Hodgdon's H110. The powder dispenser is the RCBS Uniflow:


View attachment 763160

When was the last time you took this powder measure apart, thoroughly cleaned it with alcohol or hornady one shot gun cleaner and dry lube works excellent as well as it leaves a dry film on the metallic parts. you could also use some graphite lube usually found in the door knob section of lowes or Home Depot as its used for the inside of locks. This may help.

 

[jski]

I must admit, it's been a while since I've thoroughly cleaned the beast. Usually just empty and refill. I do use compressed air when it's empty.

 

[cfullgraf]

I must admit, it's been a while since I've thoroughly cleaned the beast. Usually just empty and refill. I do use compressed air when it's empty.

If you clean off the graphite coating left on the plastic reservoir by the powder, you will go through a bout of static problems until the coating is re-established.