GemPro 250 drift

Discussion in 'Reloading' started by trueblue, Dec 6, 2017.

  1. trueblue

    trueblue Well-Known Member

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    I bought a new GemPro 250 to try and be more accurate with my reloading.
    Having trouble with this unit giving me different weights every time I take the scale pan on and off the scale ?
    Anyone else have trouble using the GemPro 250,and are there some tricks to this unit I need to know?
     
  2. Dr. Vette

    Dr. Vette Well-Known Member

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    No nearby fluorescents.
    No running computers, running electronics, nothing.
    Any nearby electrical item will cause drift. Even having a computer in Sleep mode might be enough to do it.

    In my old house I could leave the fluorescent on, but had to turn off the computer sitting on the other end of the bench even though I had line filters on both items. In the new house it just seems to drift no matter what, and it's all LED lights. I have yet to find the trick in this location.
     
  3. rcoody

    rcoody Well-Known Member

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    i have 3 of them. always used 2. one to trickle on and one to check weight.

    turn it on the night before you use it. those things take a long time to warm up. plugging it into a quality line conditioner helps a lot but a good one cost more than the gempro.

    i finally bought one of Adam's autotrickler systems. now charging cases is a pleasure.
     
  4. Mike027

    Mike027 Well-Known Member

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    I have noticed on mine that if I don't put the powder pan back on the scale soon after I dump it I will get drift. Once I dump the powder pan I put it back on the scale within a few seconds. My gempro stays consistent if I do that.
     
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  5. Barrelnut

    Barrelnut Well-Known Member

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    On my second GemPro. First started having issues after about 2 years. Have been using this on for over 3 and it is solid as a rock. I let it warm up for an hour or so. It needs a vibration free surface. It doesn't work well in cool temps. It works faster at temps over 65 degrees.

    I use a Hornady Auto Charger to throw a load and trickle up on the GemPro.
    A big thing that helps me is I put the pan on the GemPro and let it settle while I throw a charge on the Auto Charger IN ANOTHER PAN. I then dump that into the pan already on the GemPro and trickle it up. If you want to test/recheck your weight in the pan, Pour the powder back into the Auto Charger pan. Place the GemPro pan back on the GemPro, let it settle and then dump the powder back in from the Auto Charger pan. It's not as difficult or time consuming as it might sound.
     
  6. Okanogan

    Okanogan Well-Known Member

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    In addition to the previous comments, I have found my Gem Pro 250 (and my FX 120i) to be very sensitive to air currents. The air conditioner/ heater blowing all the way across the room or the window open seems to make a difference. While it might not be necessary, I also put my Gem Pro/ FX 120i on a mouse pad to try and to help isolate them a little from vibration or my own movements while weighing.
     
  7. L.Sherm

    L.Sherm Well-Known Member

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    I never turn mine off, but i use it all the time. As stated above i don't leave my pan off either.
     
  8. bigdaddyWSM

    bigdaddyWSM Member

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    I normally use it for a final weight check after my Lyman gen6 powder measure, I make sure it's warmed up & turn off shop light right above my powder station. it seems to be off .01-.03 after a while & I just zero pan again, close enough for me.
     
  9. Biggs300

    Biggs300 Well-Known Member

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    Sorry, posted this before I completed the response. See below.
     
    Last edited: Dec 8, 2017
  10. rfurman24

    rfurman24 Well-Known Member

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    I will take all the worthless units of your hands. I would start by unplugging the unit and taking the balance plate off(one screw, do not press on it. Hold it with your hands.) then the cover plate(4 screws) and make sure you do not have a kernel of powder under the beam.
     
  11. Biggs300

    Biggs300 Well-Known Member

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    Mine started drifting just a few months after I started using it. Now, I cannot get the unit to calibrate and it is useless. I have more faith in my $29.00 Frankfort Arsenal DS-750 which, I had for over two years. I check it with my RCBS 10-10 balance scale.
     
  12. rfurman24

    rfurman24 Well-Known Member

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    I would guess you have a kernel of powder under the beam.
     
  13. Biggs300

    Biggs300 Well-Known Member

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    Rfurman24, thanks for the suggestion. I removed disk covering the internal works and did not see any powder kernels and the internal works appear really clean with regard to reloading material. The scale is perfectly balanced on my reloading desk which is only used for throwing and measuring powder charges. My reloading press is on a separate bench and the GemPro gets very little jarring and is stable. I will give it another shot, but I don't have much confidence that it will work as well as it should. Thanks again,
     
  14. rcoody

    rcoody Well-Known Member

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    i had one that went crazy. sent it back and they sent me a brand new one inthe box
     
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