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My Weigh GemPro 300 Table Top Jewelry Scale

Electronic Interference Suppressor Included (An Old Will Exclusive)!
300 carat capacity x 0.005 carat resolution

"In A Nutshell"
PowerAC Adapter (included)
6 AAA Batteries (not included)
Display0.875" reverse lit display : 0.6" digits
Tare FeatureYes
CalibrationExternal : 50g
Weighing HookNo
Platform Size2.75" diameter
Scale Size4.5" x 6.25" x 3.5"
Weighing Modes6

Included Accessories

  • VibraKill® Pad - (An Old Will Exclusive)
  • Weighing Scoop
  • Hard Protective Case
  • 50 Gram Calibration Weight
  • AC Power Adapter
  • Plastic Tweezers
  • Ferrite Choke(For Electronic Interference Suppression - An Old Will Exclusive)

Weighing Modes

Mode: GramsCapacity: 60.000 gResolution: 0.001 g
Mode: OuncesCapacity: 2.11645 ozResolution: 0.00005 oz
Mode: PennyweightsCapacity: 38.580 dwtResolution: 0.001 dwt
Mode: Troy OuncesCapacity: 1.92900 oztResolution: 0.00005 ozt
Mode: Carats*Capacity: 300.000 ct Resolution: 0.005 ct
Mode: GrainsCapacity: 925.94 gnResolution: 0.02 gn

Product Details

Programmable Auto-Off Feature If you've ever had your scale turn off on ya in the middle of important measurements, you'll realize what a blessing this feature is. You can program the GemPro 300 to turn off automatically, or to stay on until you turn it off yourself.

Protective Case This little jewelry scale comes with a hard, protective case to keep your scale, along with all of its accessories, nice and safe.

Really Cool, Reverse Lit Display This precision jewelry scale has a bright, reverse lit display. You'll have no problem reading this precision scale, even in the dimmest lighting.

Man, This Thing Is Tiny! You won't have to worry about this scale taking up space. It's just over six inches long, and only three and a half inches high.

Hinged Platform Protecting Cover This precision scale has a hinged hardcover ya flip down over the weighing platform when you're not using it. This helps prevent accidental damage to the load cells.

It Remembers The Last Unit Ya Used If your application needs weights in the same unit of measurement, (like ounces for instance), it can be a real pain if your scale always turns on ready to weigh in grams. It's a good thing the GemPro 300 turns on displaying the unit of measurement you were using when ya turned it off.

Stainless Steel Platform The Gem Pro has a durable stainless steel weighing platform to make cleanup a breeze. Stainless steel doesn't scratch easily and keeps its shine without rusting or tarnishing.

Easy Calibration To make sure ya keep getting the best weight readings from your scale, it helps to calibrate it from time to time. This jewelry scale has instructions to make calibrating your scale easy. The Gempro even comes with the 50 gram calibration weight ya need to get the job done.

Tare Feature The tare button on the front of this digital scale can be pressed to "zero out" the weight on the scale. You can then add more weight, and the display will only show the weight of the items you're adding. This sure is useful when ya want to use the included expansion tray to weigh your things, or if ya want to get separate weights of multiple items.

Liquid Level Indicator This very handy feature helps you quickly and easily get your GemPro-300 nice and level. A level scale is important for getting the most accurate weight readings.

Five Useful Accessories The GemPro-300 comes with great accessories. Use Old Will's exclusive VibraKill® Pad under the GemPro to keep vibrations from messing up your weight readings, and the calibration weight to keep it nice and accurate. If you're looking to use the GemPro as a diamond scale or carat scale, the little expansion bowl is perfect for weighing those teeny tiny jewelry pieces, and the included tweezers make picking up those pieces easy. You even get an AC power adapter, just in case ya don't have any batteries on ya. You can store the GemPro300, along with the expansion bowl, tweezers, calibration weight, and adapter in the included protective storage case.

Kill Those Vibrations With VibraKill® Did ya know that vibrations can cause a scale's reading to bounce around from one weight to another? Included with this digital scale is a VibraKill® Pad to keep vibrations, (caused by everyday items like, your fridge, nearby music, your washing machine, etc...) from messing up your weighing.

30 YEAR MANUFACTURER'S WARRANTY! If ya have a problem with this scale, just send it to MyWeigh's warranty center in Phoenix, Arizona. They'll fix or replace your scale and send it on its way back to ya within a week of receiving it. You should expect your replacement to arrive in about two to three weeks from the day you send the original off. Keep in mind that sometimes MyWeigh runs out of stock, which can cause a delay in the warranty replacement process.

Product Reviews

Overall Customer Rating:
from 24 customer reviews.
My old dependable now
I bought a lot of different scales for reloading over the years. RCBS, Hornady, Lyman, a bunch of them. This little Gempro 300 is 5 times as accurate as those guys, and this guy is real dependable. Ive had mine for about 2 years now, and its still my go to. Im back here at Old Wills to get one for a friend. I hope theyre still including their special tip sheet, because that thing helped me to get my scale to behave when I first got it.
Reviewed by: Jeff in Longview from Longview TX on 5/29/2018
Very easy to set up & use
This scale did everything as advertised. It is accurate, easy to use and comes in a hard covered storage case.

Old Will Knott Scales also is proactive regarding the use & set up of the scale. They included a separate instruction sheet explaining the operations of the scale and offer to answer any questions regarding any issues with the scale.
Reviewed by: Herman R from CA on 4/2/2018
Poor Quality
First the buttons when depressed get stuck and you have to repress them so they release.

The leveling have no friction so they spin freely.

Tare is useless as its repeatability is non existent.

You set a tare and it constantly changes.

There is no phone number to contact customer service.

My Gempro 300 Failed after 8 months.

Just a poor quality scale.

Reviewed by: Harry from NY on 1/15/2018
GemPro 300
Ordered the scale and it arrived exremely fast. Communication with seller was outstanding. Scale is extremely accurate. Very happy I bought and highly recommend to any reloaders out there.
Reviewed by: raystar2 from on 10/19/2017
Excellent product! Would by again in a heartbeat. Arrived super fast! Great place to do business. I reload precision ammo and using this has brought my ES value to 11 and SD to 6.0 :)
Reviewed by: AWESOME Investment from on 9/29/2017
Do not hesitate, this lil machine is awesome!
Read the instructions and the Old Will Knott's tips and understand them clearly because most of the ticks and quirks are operator error due to the sensitivity of this device. I use it for reloading and I am wanting long range consistency and this is the hot ticket to achieve that. Shipping was fast and packaged well.
Reviewed by: Tom Wingo from Northwest Oklahoma on 7/27/2017
Do not hesitate, this lil machine is awesome!
Read the instructions and the Old Will Knott's tips and understand them clearly because most of the ticks and quirks are operator error due to the sensitivity of this device. I use it for reloading and I am wanting long range consistency and this is the hot ticket to achieve that. Shipping was fast and packaged well.
Reviewed by: Tom Wingo from Northwest Oklahoma on 7/27/2017
Scale works great. I've had a few 250's and the batteries last much longer in the 300.
Reviewed by: Dave from on 5/29/2017
My Weigh GemPro 300
For what I needed it for it works just fine. Needed a decent scale for double checking powder charges for my pistol reloads
Reviewed by: rrbigronn from Bristol on 5/11/2017
GemPro 300
<p>Received my GemPro 300 and after testing I returned for refund. I didn't have a drifting problem just repeatability problem. No matter what I weighed it would not return to zero or weigh the item the same.</p><p>Customer service is great and I might try another!</p>
Reviewed by: JD from NC on 3/26/2017
Gempro 300
I haven't had a lot of opportunity to use it yet, but it calibrates easy, very consistent readings when weighing the same item over and over. Easy to read display.
Reviewed by: Sid from on 3/7/2017
Final GmPro-300 Test
I ran a larger test based on the best of the last ones. No more testing, I'm done! I did 2 different weights alternating them encase it had a memory effect and using Tare each time. (All test were done leaving a small powder pan on when resetting to zero) After 26 weights, the scale refused to return to zero so I had to restart it.

35.62g x 3 35.50g x 4

35.64g x 16 35.52g x 11

35.66g x 6 35.54g x 10

Then ran the 1st weight turning the scale on and off each time.

35.62g x 2

35.64 x 14

35.66 x 9

Looks like using Tare is as good as anything else and using this method, the readings are all within a .04 grain group in 3 test with 75 separate weights. For the money this as good as it gets. Hope this info helps everyone.
Reviewed by: Reloader Tom from on 3/7/2017
This is an update to my previous review. This scale is usable if you work with it. Not as simple as turning it on and just weighing. I've tried everything I can think of. I tested with 4 different weights alternating them on the scale in grains. I turned the scale on with the pan so it zero'd that way. This was run 7 times or 28 weights each. A .223 bullet (74.94/75.04), A .308 bullet (207.80/207.90), Lead shot ball (35.46/35.56), Foam ear plug (9.16/9.22) 3 of the 4 had a full 1/10g variance. Same test except using TARE between each change. It cut the variance down over 1/2 with 3 being within .04g and the ear plug at .02. Another test using 2 pans and 2 slightly different weights alternated. I zero'd without the pan. Pan #1 (141.54 x 1), 141.56 x 7), (141.56 x 2). The second pan, (141.70 x 5), 141.72 x 5). The most repeatable was turning the scale off between readings. 11 tries, 141.56 x 1), (141.56 x 9), (141.58 x 1) 9 out of 11 seems good. Also I tried weighing individual pieces of Varget powder using TARE each time. from 0-2 no reading, from 3 to 12 it showed .02 per piece. I added 13 more for a total of 25 and it read .54g. Added another 25 and it read 1.06g. Those pieces of powder look close but aren't all the exact weight. So far you have to TARE between each weight or it drifts. I also compared with a Hornady Autoloader. 29 loads set to 40.0g and checked with the GM300 using TARE each time. Should be good for a .04g accuracy window for comparison. 19 of the 29 fell into a 0.10g group, 24 of the 29 into 0.14g and a total spread of .36g from (39.82 to 40.18). Didn't show "overcharge" on the 40.18 and a 40.10 load. Definitely can't trust it without verifying the readings with a more accurate scale.
Reviewed by: Reloader Tom from on 3/6/2017
Useable if you are willing to work with it.
I just got this scale yesterday. Initially I was ready to send it back but wanted to give it a fair test. Yes, I had trouble with it drifting and not returning to zero. Here is what has worked for me so far. Turn the scale on for at least an hour. The scale is much more accurate if it is perfectly level too. Don't use the little level inside it. Get a decent small bubble level and level it front to back and side to side from the weighing surface (under the stainless cover on the black plastic surface, because the metal cover is not 100% flat on top). Another problem I was having was it refused to return to zero even after pressing the TARE button several times. The trick was to put the powder pan on the scale, turn it off, and back on. It stayed on zero for 7 hours only needing reset once. Also noticed that if you sit something on the scale with any impact (I'm talking a 75 grain bullet dropped into the pan from 1/4" up) to setting it down like a feather, it read .02g grain difference. Easier gave the lighter reading. And you can't trickle into a pan. The scale tried to stabilize the reading and it won't pick up small changes. Best way is to add a tiny amount, then pick up the pan and set it on the scale again getting a refreshed total reading. So far? but every other inexpensive scale on the market does the same thing until you spend 4X as much. Still in the testing phase. I'm going to reload some tomorrow using a Hornady Autocharger and use this scale to check and correct the loads. The Hornady was hard to use until I figured out it's quirks. It works better with fine powders but you still can't trust it, sometimes getting a full 1/10 grain over or under your setting.
Reviewed by: Reloader Tom from on 3/3/2017
This scale is great compared to my old balance scale. It drifts a little. I just tare it or zero it.
Reviewed by: Jesse from on 2/27/2017
Save your time and money buy something better!
I purchased the Gempro 300 in hopes of upgrading from my current 2 reliable PACT reloading scales. I'm a competative long range 1000 yard shooter who's always looking for a way to gain an advantage in producing more accurate handloads. THIS SCALE FAILED HORRIBLY IN DOING SO! I was very pleased with the Gempro at first. Nice packaging, solid platform, ease of instruction, decent check weight, but then I started reading the "Tips sheet" and wondered what had I just got myself into? I followed the "tips sheet" to a T (who weighs gun powder in a bedroom or bathroom?) and here's my result. The fun didn't really start until well after I plugged it into a power source. I gave it a full day to warmup to room temperature before testing. I know to expect a little drift at first due to the exteme sensitivity of weighing to .02gr, but this drift was unbelievable. It would drift .30gr with nothing on the scale. I thought I was seeing thinge at first. In all my experience of working with electronic scales there's no way there should be drift nearly half a grain from zero with the wind cover closed. I then decided to set the scale back to weighing grams with MY verivied and certified 50g check weights. By the way, the check weight that was included with the scale was not a true 50g weight it was lighter. The GP300 could not repeat a weighing of the same 50g weight, nor could the tare weight of 50g hold true. I messed with this scale for 3 days with the same results. True definition of insanity! After hours of wasted time and being extremely frustrated I threw in the towel, packed up the scale and made the call to customer service.

Anyway one positive; the folks at Old Will Knott Scales were super understanding and very easy to work with on this issue. The scale is heading back to them now and im going to return to using my proven PACT reloading scales. By returning to my tried and true scales I'm only giving up possibly 1 to 3 kernels of powder load to load. At 1000 yards wind has always been more of a determing factor on group size than that amount of gunpowder will ever be.

Bottom line....I dont recommend this product, but I do recommend Old Will Knott Scales.

Reviewed by: Andy from PA on 2/4/2017
Bought this for reloading as an upgrade to my RCBS 1500 which resolves to +/- .1 grain as compared to +/-.02. At first, everything was great. The scale worked as advertised, I couldn't have been happier. Then the problems started. After about a month, I noticed if you weighed the same object multiple times, the weight would vary by more than .02gr;and as time went on,this amount got larger. This is when the scale also wouldn't return to zero.
Reviewed by: Loader10 from on 2/2/2017
Good little scale

The display is very easy to read.

Adjustable feet to level the scale.

Battery or A/C power.


Buttons sometimes feel a little sticky.

Reviewed by: tjm2005 from Ohio on 1/15/2017
Gem Pro 300
2nd Review, After reseting my work area leveling and room Temp. to 71 degrees and warm up time on scale . The scale was much better. It still has to have the Tare reset from time to time .

I am using this for reloading it is fun to add one grain of Varget and see the scale adjust.
Reviewed by: Don Bend Or. from Bend Oregon on 12/30/2016
Gem Pro 300
I love the size compared to the 250. I am using it for reloading, as of now it is floating and the tare button is getting a workout. I am also getting a Error ------5 from time to time ?

It is very cold here right now keeping my shop at 70 is hard.

I do hope as temperatures warm it will settle ?

I will give a follow up in time.
Reviewed by: Don from Bend Or. on 12/21/2016
Works good. Has some zero drift but not excessive
Reviewed by: jerred90 from on 10/17/2016
GemPro 300 review update
This is an update from my last review. I have been using the GemPro 300 for a few months now. This scale is working great, almost no drift and can weight a single kernel of Varget. I am setting tare with nothing on the scale then adding the weight of the charge and powder pan for my target weight. I was setting tare before with the pan on the scale and was experiencing a lot of drift. Now there is almost no drift and the scale is working great.
Reviewed by: Jeff from Pennsylvania on 7/3/2016
I have been using the GemPro 300 for a few weeks now. The GemPro is more accurate than my Hornady M scale. The only issue that I have with it is that it drifts. For the price it is pretty good. Your other option is to spend a lot more and go to Electromagnetic Forced Restoration.
Reviewed by: Jeff from Pennsylvania on 5/23/2016
Good scale for the money
Just got done reloading 100 rounds with is scale and.. It has a fast stability time. I say faster than the GemPro 250 The screen is very easy to read thanks to a bigger screen and better screen angle (so no more hovering over the scale) I say the accuracy is better than the 250. The 300 at times was picking up a single kernel of powder and it was always picking up two kernels I didn't see this scale drift once. But 3 - 4 times out of 100 it didn't catch a couple of kernels dropping into the pan so I just pulled the pan off and the replace it and boom it did. For the money I think this scale is a better buy other than the 250. Its not the best scale but it sure works fine for the money!
Reviewed by: Jeff Lundgren from Nebraska on 4/21/2016

Product Questions

Number of questions: 0

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