Picking a Digitial Scale

So after getting gouged up on balance beam scales, I'm on the hunt for an inexpensive Ohaus scale to send Scott Parker.  In the interim I need to pick up an accurate and reliable digital digital scale.  Some great inputs on the forum, but I found a couple of other options and wanted to toss them out there and see if anyone had experience.

Cheers,
Derek


Bald Eagle BE1188 Digital Powder Scale
$79.95
.020 gr accuracy
http://www.grizzly.com/products/BE1188
http://benchrest.com/showthread.php?92591-New-scale-affords-opportunity-for-measure-technique-refresher-practice
http://forum.accurateshooter.com/index.php?topic=3865806.0







My Weigh GemPro 250 Digital Scale
$129
.020 gr accuracy
Lifetime Warranty
http://www.brownells.com/reloading/powder-handling/powder-scales/gempro-250-precision-scale-prod59271.aspx
http://www.accurateshooter.com/gear-reviews/gempro-250-digital-scale-review/
http://myweigh.com/product/gempro-series/
https://www.preciseshooter.com/blog/ScaleReduxPart3GemPro250.aspx









American Weigh GeminiPro GPR-20 Digital Powder Scale
$56
No AC Adapter
.020 gr accuracy
10 Year Warranty
http://www.americanweigh.com/product_info.php?products_id=2116

http://www.awscales.com/portable-precision-scales-01-gram/247-geminipro-digital-milligram-scale

https://www.preciseshooter.com/blog/ScaleReduxPart2GPR20.aspx

I have the.gem pro . It's a good scale. You want to let it warm up and calibrate before each use.

I've been using the Gem Pro 250 for years now. At first I always used it alongside my trusty Ohaus 10-10, but have slowly come to trust the digital one enough to just spot-check it against the 10-10 from time to time.

I do leave the Gem Pro powered on 100% of the time though, it is always stable and ready to go that way, otherwise it needs some warm-up to stabilize.

I've had success with with unit:

http://www.amazon.com/gp/product/B0012TDNAM?psc=1&redirect=true&ref_=oh_aui_detailpage_o02_s00

You have to let it warm up to room temperature but after that its stable and repeatable.  I haven't tried it with a powder trickler and I suspect that it may not work.

For $25.00 it's pretty hard to beat

if you can find the original version of dillons, it has 4 button on front, it was made by ohaus and is very accurate. the current version is made by autolab and not as good imo,  here is one on ebay right now.


http://www.ebay.com/itm/Dillon-Precision-D-Terminator-Electronic-Digital-Reloading-Scale-/121743427393?hash=item1c58794741

If a scale is accurate to 0.1gn, it is more than adequate for any demanding pistol ammunition and, I would bet, any rifle ammunition.
I have never had a digital scale I didn't like. I still have the Ainsworth I bought back in the '70s.
I would consider about $65 to be the minimum price for a decent scale--beam or electronic. Scale should have a "wind shield" so drafts don't upset the reading.
If you want to be OCD, spend the money for a real laboratory micro-balance capable of reading to 0.5 mg.

noylj you are absolutely correct in bench rest shooting most shooters never use a scale ask them what they load and they will tell you number of clicks on a harrell's measure.

So my question involves stacking of tolerances.  Let's say my scale is perfectly calibrated (it probably isn't) and I then measure the charge to +/- 1/10 of a gr which is dispensed by my Dillon 650 which is good to +/- 1/10 of a gr.   Could I n theory be off by as much as 2/10 of a grain?  If that is the case it would be relevant I assume or am I totally off base?   I would assume you would want to have as accurate an assessment as possible to minimized the deviation already induced by the progressive reloader.

depending on the powder, you can survive much larger variations than .2 grains....

With Titegroup/BE there was a pretty big spread in accuracy in my RO with a .2 gr change in the load with the factory barrel.   Now that I have a Kart barrel being installed, maybe that will change.

JayhawkNavy02 wrote:So my question involves stacking of tolerances.  Let's say my scale is perfectly calibrated (it probably isn't) and I then measure the charge to +/- 1/10 of a gr which is dispensed by my Dillon 650 which is good to +/- 1/10 of a gr.   Could I n theory be off by as much as 2/10 of a grain?  If that is the case it would be relevant I assume or am I totally off base?   I would assume you would want to have as accurate an assessment as possible to minimized the deviation already induced by the progressive reloader.

  I'll start off by assuming you'll be loading on a progressive press and not weighing individual charges.  If this is not the case, stop reading now

  The following comments and observations are based on data I collected.  I am not a statistician, but I do work with them on my day job.

  On my Dillon RL550B, the weight of Bullseye and Winchester Super Target dropped charges have a Standard Deviation (SD) about equal to the Probable Error of my PACT BBK scale, ~0.05 grains.  Nominal charge weight was 4.5 grains. That is to say, ~66% of dropped charges will have a deviation from the nominal charge weight that is too small for my scale to measure.  95% will be within +/- 0.1 grains of the nominal weight, and >99% will be within +/- 0.15 grains. (The scale was calibrated with the check weights that came with the scale.)

  As a practical matter there isn't much you can do to make SD smaller with a given powder.

  So, the questions are-

a.  What is your tolerance?  Do you know if it matters?
b.  How much effort are you going to expend identifying and recharging the rounds that are out of (your) tolerance?
c.  How lucky do you have to be to find the ~1 in 200 that is farther off than 0.15 grains?

Rich,

I'm loading on a Dillon 650 and I assume (correct me if I'm wrong) the precision in the powder dispenser between the 550/650 will be roughly equivalent.   Appreciate the Objective Quality Evidence (OQE), that's enlightening.  Not a statistician either, but took several classes in Engineering school and didn't enjoy any of them...   I'm very happy to hear the precision is as good as it is.

My goal is to ensure that my throw is as close to the amount that I desire and to check that throw as accurately as possible at some point during the reloading process.  I won't be weighing each round, just validating my setup is within spec.  

a. Objective is +/- .1 not to exceed +/- .2 
b. I'm not sure I can detect/observe a deviation that small visually to know when to re-weigh/adjust the drop.
c. I agree that is impossible, other than randomly weighing 1 in 200 and catching a change in setup.

Thanks again for the great advice and help.  This forum has always been a terrific source of knowledge.

Derek

I know this doesn't help you with a digital scale but I did put a powder baffle from big Bike Parts in my Dillon 650 and I'm amazed as to how much it helped in keeping my charge consistent. There are other people here on this site that are using it also.

http://www.bigbikeparts.com/templates/product.aspx?ProductGuid=6-101&GroupGuid=2015


Virgil

+1 on a good baffle in the Dillon tubes

I have used this one on both my Dillon 550s with excellent results

http://www.uniquetek.com/site/696296/product/T1278

Have either of you measured the throws before and after the baffle to see if there is any measurable difference in performance?

The other question, is it worth pursuing the UniqueTek Micrometer Powder Bar Kit given the accuracy described with the OEM powder bar? 


http://www.uniquetek.com/site/696296/product/T1231

Yes on the powder bar. It seems to increase the consistency of the thrown charges quite a bit and the micrometer is nice when you want to repeat a setting.

Best thing I've done to my 450/550.  It is really nice to dial up a setting and have it within a tenth or so right off the bat.

NO question it improved consistency

If you are a rifle loader it really helps with large grain powders

Flak type pistol powders throw much better

The above referenced the baffle

Haven't tried the powder bar yet but it's on the list

Yes on trying the charges on the powder baffle. I use to get + - .01 either way which equals .02 total with the Dillon baffle and now I get dead on 99 out of 100 times with the new baffle.


Virgil

WoW!  That's amazing, and that's with the Bike Parts.  I wonder if there is any difference with Unique tek or they do the exact same thing equally well.

JayhawkNavy02 wrote:
My goal is to ensure that my throw is as close to the amount that I desire and to check that throw as accurately as possible at some point during the reloading process.  I won't be weighing each round, just validating my setup is within spec.  

a. Objective is +/- .1 not to exceed +/- .2 
b. I'm not sure I can detect/observe a deviation that small visually to know when to re-weigh/adjust the drop.
c. I agree that is impossible, other than randomly weighing 1 in 200 and catching a change in setup.

Thanks again for the great advice and help.  This forum has always been a terrific source of knowledge.

Derek

a.  With a powder that meters as consistently as Bullseye and WST, you can expect ~95% of dropped charges to meet your criteria.
b.  I'm sure you can't look into a case and visually detect a 0.2 grain difference in a powder charge.
c.  The likelihood of picking one out of 200 and it being The One is pretty remote.

Adjust your powder dispenser so that ten dropped charges weigh ten times what you want one to weigh, and then keep your hands off the adjusting nut!

Virgil Kane wrote:Yes on trying the charges on the powder baffle. I use to get + - .01 either way which equals .02 total with the Dillon baffle and now I get dead on 99 out of 100 times with the new baffle.


Virgil

Forgot to mention that this was with Bullseye powder.


Virgil