Most Accurate Powder Scale ?

[Frankr]

I don't know much about scales but could there be a scale that works as well as the FX120i at half the price?
I was looking at a A&D Newton EJ-123 as a good scale. At 339.90 The FX120i at 646.80 is it the magnetic force deal that makes the difference,

 

[Twoboxer]

I have no experience with the Newton. Looking at the specs, it seems part of the $340 price (vs $125 GemPro 250) may be for features I don't think a handloader uses - checkweighing, counting, sealed keyboard, and percent weighing - although those are all software related lol.

Without a trial period for the A&D Newton, I personally would stick with the GemPro 250 and its flaws. Or wait until I could get the FX120i. This will sound funny, but I'd be careful about recommendations . . . I bought 7 scales and a lab grade power supply that way before finding the A&D.

Yes, mag force makes the difference. The strain gauge is the source of the issues. My understanding is that Strain Gauges are often referred to as "RF Noise Receivers" rather than balances. As for the other issue, the gauges used do not have enough divisions to cover the range they are designed for. Perhaps if a scale was designed for 0-150 grains, it might work better for powder . . . but there'd still be the noise issue.

BTW, the FX120i is $530 from cambridge environmental (listed at $710 Canadian = $530 US).

 

[calgarycanada]

I think one of these days I'm going to test how much this powder weighing really matters... It wouldn't be hard to do at all.

Take a known good load with low SD. Load up 10 rounds, weighing to the kernel.

Then load up 10 rounds with randomly variable powder weight charges. Go shoot both strings and compare the SD and vertical... they might not be as bad as you expect.

To get yourself a list of random charge weights, use MS Excel. Enter the formula listed at this link....

http://smallbusiness.chron.com/generate-random-variable-normal-distribution-excel-74203.html

where B2 is the target charge weight in grains and B3 is the standard deviation of your hypothetical crappy scale.

If you are going to try it, I suggest you load 10 rounds at charge weight, 10 rounds 0.02 grains below charge weight and another 10 rounds 0.02 grains above charge weight. That would represent most good scales (like gempro 250) available today.
Shoot them 5 rounds of each set at a time on same target(at 600 to 1k) and see if you print 3 distinctive groups on same target. Color the bullet tips to see where each charge weight bullets landed.

 

[blade]

I will keep my 505 rcbs scales. I just use digital to get close and fine tune on the beam scale. Each to his own.

 

[Sheldon N]

I will keep my 505 rcbs scales. I just use digital to get close and fine tune on the beam scale. Each to his own.

My own testing with check weights and trickling powder charges with multiple digital scales and my RCBS 505 indicated that my 505 scale was not nearly as accurate as the digitals.

 

[Endyo]

My own testing with check weights and trickling powder charges with multiple digital scales and my RCBS 505 indicated that my 505 scale was not nearly as accurate as the digitals.

German Salazar had similar results testing a balance scale vs electronic scales.

To the OP:

A Gempro (strain gauge) will be an affordable upgrade and possibly all you need.

Trickling up to target weight is where the magnetic force shine.

 

[fguffey]

I have scales; I have 2 sets of check weights from Ohaus. Both sets have 46 pieces of check weighs in each. I also have other weights. I do find it difficult to make the weights agree. Meaning I can calibrate one scale with one weight then test another weight that weighs the same and then have to decide which weight I am going to use to get all of the scales to agree. I did separate the weights that do not agree; most of the weights that do not agree came with the scale as a check weight.

F. Guffey

 

[blade]

My own testing with check weights and trickling powder charges with multiple digital scales and my RCBS 505 indicated that my 505 scale was not nearly as accurate as the digitals.

there is a trick to getting them to stay zeroed. If you dont mount it down to a tab

My own testing with check weights and trickling powder charges with multiple digital scales and my RCBS 505 indicated that my 505 scale was not nearly as accurate as the digitals.

You have to mount it to a solid surface and not move it. If you move it the slightest bit it will change the zero. I made a bracket to mount it down to the table. Its spot on every time.

My own testing with check weights and trickling powder charges with multiple digital scales and my RCBS 505 indicated that my 505 scale was not nearly as accurate as the digitals.

 

[BillPa]

You have to mount it to a solid surface and not move it. If you move it the slightest bit it will change the zero. I made a bracket to mount it down to the table. Its spot on every time.

 

[Sheldon N]

You have to mount it to a solid surface and not move it. If you move it the slightest bit it will change the zero. I made a bracket to mount it down to the table. Its spot on every time.

How do you know that it's spot on? What have you cross referenced it against?

I still have my 505 on my loading bench, sitting on a VERY solid level platform. It's not an error in my usage methods that's causing the inaccuracy in my scale. I just double checked my prior tests to make sure...

Cleaned the knife blades with alcohol to remove any residue or dust. Zeroed the scale with the pan on, checked several times, and put a few pieces of tape on the base to ensure that it wouldn't slide around or move at all.

Threw then trickled up 7 individual charges of Varget with a target weight of 42.0g. Used an Omega trickler to add the powder kernel by kernel. I even got out one of those hand held blower bulbs and would lightly blow on the scale to get it moving again to make sure the resting point settled at the center point as best as possible. The scale is right at eye level so I'm able to closely observe the marking line on the beam arm being centered against the reference line. This methodology is about as meticulous and precise as I can be.

I then cross referenced these charge weights against my digital scale (Acculab VIC-123) and used a check weight each time on the digital to rule out any drift. The Acculab registers down to .02g and I have found it accurate to +/- 0.02g.

Here's what I got for measured charge weights from the RCBS 505 scale.

42.06
41.98
41.98
41.92
41.90
42.04
41.96

Now I'm not saying that all beam scales are bad, just that my 505 scale is not particularly impressive. Infer from this what you will.

 

[blade]

How do you know that it's spot on? What have you cross referenced it against?

I still have my 505 on my loading bench, sitting on a VERY solid level platform. It's not an error in my usage methods that's causing the inaccuracy in my scale. I just double checked my prior tests to make sure...

Cleaned the knife blades with alcohol to remove any residue or dust. Zeroed the scale with the pan on, checked several times, and put a few pieces of tape on the base to ensure that it wouldn't slide around or move at all.

Threw then trickled up 7 individual charges of Varget with a target weight of 42.0g. Used an Omega trickler to add the powder kernel by kernel. I even got out one of those hand held blower bulbs and would lightly blow on the scale to get it moving again to make sure the resting point settled at the center point as best as possible. The scale is right at eye level so I'm able to closely observe the marking line on the beam arm being centered against the reference line. This methodology is about as meticulous and precise as I can be.

I then cross referenced these charge weights against my digital scale (Acculab VIC-123) and used a check weight each time on the digital to rule out any drift. The Acculab registers down to .02g and I have found it accurate to +/- 0.02g.

Here's what I got for measured charge weights from the RCBS 505 scale.

42.06
41.98
41.98
41.92
41.90
42.04
41.96

Now I'm not saying that all beam scales are bad, just that my 505 scale is not particularly impressive. Infer from this what you will.

I work in quality control and have access to alot of precision measureing equitment includeing scales. I have crossed referrence to 3 or 4 different scales at work. A little 3 in 1 oil on the pivot arms helps tremendously. Im not as much concerned about the actual weight as i am the repeatability. The digitals are just to sensitive for my likeing. Nothing wrong with them. I just prefer the beam scales.

 

[blade]

How do you know that it's spot on? What have you cross referenced it against?

I still have my 505 on my loading bench, sitting on a VERY solid level platform. It's not an error in my usage methods that's causing the inaccuracy in my scale. I just double checked my prior tests to make sure...

Cleaned the knife blades with alcohol to remove any residue or dust. Zeroed the scale with the pan on, checked several times, and put a few pieces of tape on the base to ensure that it wouldn't slide around or move at all.

Threw then trickled up 7 individual charges of Varget with a target weight of 42.0g. Used an Omega trickler to add the powder kernel by kernel. I even got out one of those hand held blower bulbs and would lightly blow on the scale to get it moving again to make sure the resting point settled at the center point as best as possible. The scale is right at eye level so I'm able to closely observe the marking line on the beam arm being centered against the reference line. This methodology is about as meticulous and precise as I can be.

I then cross referenced these charge weights against my digital scale (Acculab VIC-123) and used a check weight each time on the digital to rule out any drift. The Acculab registers down to .02g and I have found it accurate to +/- 0.02g.

Here's what I got for measured charge weights from the RCBS 505 scale.

42.06
41.98
41.98
41.92
41.90
42.04
41.96

Now I'm not saying that all beam scales are bad, just that my 505 scale is not particularly impressive. Infer from this what you will.

if you just sit it on a table and try to use them you will never get any kind of precision repeatibility. That have to be fastened down and where they absoulutely can not move the slightest bit. My bench is on castors. I learned this the hard way. I could set the zero and roll my bench slightly and watch the zero point change. I strapped it down to a permenant structure and shimmed the adjustment foot and it took care of the problem. The most i have ever had it get off zero since then is about the weight of 1 kernel of powder.

 

[blade]

if you just sit it on a table and try to use them you will never get any kind of precision repeatibility. That have to be fastened down and where they absoulutely can not move the slightest bit. My bench is on castors. I learned this the hard way. I could set the zero and roll my bench slightly and watch the zero point change. I strapped it down to a permenant structure and shimmed the adjustment foot and it took care of the problem. The most i have ever had it get off zero since then is about the weight of 1 kernel of powder.

another thing is your dealing with alot less surface area with that small pan. Less area to catch a draft.

 

[BillPa]

You have to mount it to a solid surface and not move it. If you move it the slightest bit it will change the zero. I made a bracket to mount it down to the table. Its spot on every time.

I've posted this pic of my tuned 505 before...

The angled pins one each front that back locate the right end of the scale. What can't be seen is the bushing for the leveling foot 'nub' to ride in. Between the pins and bushing the body can't move side to side, front to back. I can remove it, put it back on without the need re-zero it.
Bill

 

[blade]

I've posted this pic of my tuned 505 before...

The angled pins one each front that back locate the right end of the scale. What can't be seen is the bushing for the leveling foot 'nub' to ride in. Between the pins and bushing the body can't move side to side, front to back. I can remove it, put it back on without the need re-zero it.
Bill

SWEET!

 

[Frankr]

well I have a old RCBS powder pro digital scale I think it was the first one they made I have had it for 20 years. I hardly use it because of the drift..but I have got used to it and I can tell when it re tare's the pan and will change or stay. I don't know how accurate it is but it takes three small powder sticks to move it .1 . But my 10 10 a NJ scale I loaded up some loads shot well decent numbers..came back reloaded the same thing and went out shot poor and the numbers were bad..I have been loading since I was 16 years now 50 years old..I broke out the dig scale and sure enough that 10 10 was .4 off heavy then another time it was .4 off light..I have the 505,10 -10. redding bullet master ect..all the beam scales stick and do not weigh consistently..I had the original scale I got when I was 16 years old it was the RCBS that was below the 505 and it was the best scale I ever had. I gave it to my brother in law because I had better scales now HA! ..I think I will work on the 10 10 and buy a gem pro to test it and keep it tuned. I just cant spend the money on a FX 120i right now.

 

[bloc]

Rcbs 304 scale. Hard to find and pricey. Just sold mines for $600 shipped.

+1

I paid, I believe, something short of $300 for mine back in the . . . what . . . late '80's?. I never anticipated it would serve so well.

But just try to pry it out of my cold, dead hands!