Balance beam scale vs digital

Discussion in 'Reloading' started by johngfoster, Oct 16, 2007.

  1. johngfoster

    johngfoster Active Member

    Messages:
    30
    Joined:
    Sep 13, 2007
    I've been getting frustrated lately. I have been trying to sort my Lapua brass by weigt prior to priming/loading using my RCBS 5-0-5 balance beam scale, but have been getting inconsistent results. The exact same case can differ by as much as 0.2-0.3 gr upon a re-weigh. And it takes forever to weigh a case, waiting for the beam to settle down. Would I be better served by a digital scale? I think it would be quicker, but would it be more accurate and consistent?

    Thanks,

    John
     
  2. Steve Shelp

    Steve Shelp Well-Known Member

    Messages:
    351
    Joined:
    May 3, 2001
    John,
    I have both scales (Redding balance beam and an Ohaus Navigator Digital) and you should be able to get the same consistency/repeatability from both. The one statement that really bothers me in your original question is that you can reweigh the same case on your balance beam scale and you get a 2-3 tenths difference in weight. That is an real issue!
    Double check the area around where the dampener is and make sure there isn't anything stuck to the magnet that would influence the raising and falling of the beam. I use 0000 steel wool to clean my necks and I have found times when 1 or 2 strands of the steel wool will find their way to this magnet. You will see an abnormal up/down pattern in the balance beam though when weighing. Also make sure there are no burrs on the fine edges of where the beam rotates. The fulcrum points. If there is a small burr or something there impeading the beam, it will give irratic readings also.
    So check out your scale for problems first. There is something there. A balance beam works on simple physics. You should be able to weigh a case and be able to pull it off and replace it in the pan 10 times in a row and get the same reading. If not something mechanical is wrong your scale. One other thought is that if you have an A/C vent in your loading room, cut it off while weighing. Air flow will cause the beam to bounce also.

    But to answer your simple question if the beam scale is working properly they both have the same accuracy, but the digital scale is faster for checking weights of components hands down. But it won't be more accurate.
    If you do get a digital scale, be careful when using other electronic devices or flouresent lights around it. They can influence the electronics of the device with the magnetic fields. My gunsmith and I were talking and Dave was on his cordless phone while weighing charges on his digital scale. He kept saying, "something isn't right". Come to find out when he got to close to the scale with the cordless phone it would go haywire.

    So check out your beam scale first because something is wrong there. If you still interested, the digital will work just as good but faster for repeat weighing of components. I always use my beam sclae to double check my electronic scale for a piece of mind.
    Keep in mind I've never messed with the cheaper digital scales from the major reloading companies. I had heard good bad and indifferent stories about them. So I saved and spent the extra money for a good one. Not for the extra resolution it gives (.05 gr resolution) but the actual repeatability of the scale. My digital scale has always been on the money after it warms up. When I'm going to start weighing with it, I always plug it in about 1/2hr before use.

    Steve
     

  3. CatShooter

    CatShooter Well-Known Member

    Messages:
    1,053
    Joined:
    May 8, 2001
    There is no reason that the beam balance should be reading .2 to .3 off on the same case, unless you are doing something wrong.

    Digital scales are preferred for weighing cases, faster and fool proof.

    I use a digital for sorting cases, but a beam for weighing powder.

    .
     
  4. Andy W

    Andy W Well-Known Member

    Messages:
    47
    Joined:
    Apr 17, 2006
    If you end up going the digital route, do yourself a favor and buy the Acculab!
    It is great for weighing cases.

    AW.
     
  5. BountyHunter

    BountyHunter Writers Guild

    Messages:
    4,803
    Joined:
    Jun 13, 2007
    www.6mmbr.com blog archive article on tuning beam scales. June 06

    RELOADING--Tuned Balance Beam Scales by Parker: Is your electronic scale giving you the blues? Does it drift with temperature or not hold accuracy tolerance? Scott Parker can modify balance beam scales to enhance sensitivity and more importantly, repeatability. Scott tells us: "You can literally count kernels with these scales--after tuning, the scales typically gain a half order of magnitude in sensitivity and a full order of magnitude in repeatability. Outside of a $250+ laboratory scale, a tuned beam scale is the most accurate and precise balance you can buy. I have tuned several 10-10s. They all have turned out very sensitive, consistent and hold linearity like a dream. The sensitivity after tuning is such that one kernel of powder registers a poise beam deflection. For repeatability, I remove the pan and replace it for the zero 10 times. The zero line and the poise beam balance line must coincide for each of those 10 tries. I then set the poises to read 250.0 grains. I remove and replace the pan 10 times with the calibration weight. For repeatability, the poise beam balance line must return to that same balance point ten times. I then adjust the poises back to zero and recheck the zero. A report is generated detailing the initial inspection of the balance, the corrective actions performed and any remaining concerns. I sell Ohaus type 10-10 and model 5-10 scales for $70.00 + shipping. I can also modify your existing 5-10 or 10-10 scales for $20.00 + shipping. Email me at VLD223@yahoo.com or call (661) 364-1199."

    The digital is definitely faster sorting cases, but most have issues with errors for powder unless you get into the top end models. there have been several tests documented on 6br on some of the top end digitals. I use the Oahus Navigator.

    Several guys have had Scott Parker work their scales and reported good results

    BH
     
  6. specweldtom

    specweldtom Well-Known Member

    Messages:
    1,066
    Joined:
    Jun 7, 2004
    Find out what's wrong with your beam scale, or replace it. The digital scales are at least 10x faster than a beam scale for weight sorting, but the beam scale gets the last word. If my digital ever fails to zero during use, I re-zero and check the case or bullet on my beam scale. And like Catshooter, I weigh all powder charges on the beam scale. Check your beam scale regularly with the test weight. You have to have absolute confidence in it. I use the 250gr test weight that came with the Ohaus beam scale to test my digital also.

    Be sure no air is moving over either scale while you're using them. Also, don't breathe on them. Either one can hunt more than 2 tenths of a grain just from your breath.

    You will really appreciate a good digital scale if you get one, but only if you can depend on a beam scale to check it with.

    Good luck, Tom