13 Tips for Electronic Powder Scale Accuracy

Cartridges of the World, 12th Edition. Click here to order.
Cartridges of the World, 12th Edition. Click here to order.

Tip #7: Static Electricity & Magnetic Fields

Static electricity near an electronic scale can affect measurement accuracy just as much as a stray air current. Always use a powder pan made from metal or from static dissipative plastic (e.g. the Lyman Powder Pal™ or RCBS Scale Pan/Powder Funnel). PACT recommends washing their powder pan occasionally with soapy water and allowing the soap film to dry on the pan. The soap film helps dissipate static electricity.

Keep any plastic materials away from the scale, including plastic loading blocks, die storage boxes, ammunition storage boxes, AkroBins and anything made of Styrofoam or vinyl. Keeping a clear space around the scale is generally a good practice anyway. Don’t forget the static on your body! Even though the days of the polyester leisure suit are (thankfully) long gone, you may have carpet under your reloading bench.

I’m sure we’ve all scuffed our shoes across a carpet and then zapped some poor unsuspecting soul with a big arc of static electricity. A static spark to electronic powder scale is not only bad for accuracy; it can destroy the scale’s circuits! Even if you don’t build enough charge to cause a spark, you can build enough charge to affect your powder scale’s accuracy.

Fortunately, little anti-static laundry spray (Static Guard) applied to the carpet periodically is very effective. Touching a grounded metal object once in a while will also remove any charge from your body. Scales can also be strongly affected by magnetic fields and electrical interference generated by electronic devices. Don’t use a scale near any electronic device such as a computer, monitor, radio, or cell phone. Fluorescent lights can also generate interference. If you are experiencing a problem with your scale, test it with nearby electronics and lights turned off.

Tip #8: Checking Zero

Use that zero (or “tare”) button … frequently! I always zero the scale immediately before every measurement. Some may feel this is overkill, but I feel it is worth the few extra seconds it takes to ensure the best measurement accuracy I can obtain from my scale.

While we are discussing the Tare button, let’s look at just how handy this feature can be. The most basic use is to “tare” the weight of your powder pan so the scale reads 0.0 grains with the empty pan in place and the scale will display the weight of just the powder charge. This same technique can also be used for sorting bullets, cartridge cases or even loaded cartridges.

Example 1: Lets say you want to sort a new batch of bullets by weight relative to a favorite bullet weight you know from a previous test is ideal for your cartridge. If you were smart, you would keep a sample bullet from that earlier batch that is the ideal weight. Keep it wrapped in a piece of soft cloth and in a small bottle with a label on the outside noting the manufacture, type and weight and anything else you want to record. 1. Press Tare to zero the scale. 2. Place the example bullet on the scale and check that it weighs what you expect. 3. With the example bullet still on the scale, press tare to zero the scale then remove the example bullet. 4. Start weighing bullets from the new batch. Bullets that are an exact match will weigh 0.0 grains. Sort the bullets into weight groups depending on how close you need them to be to the example bullet weight.

Example 2: If you have a sneaking suspicion that you may have double charged or not charged a cartridge, just tare the weight of a known good cartridge and then start weighing the suspect cartridges. All the good cartridges should weight 0.0 grains (or very close too it). So all you need to do is look for one that weighs too much or too little by the weight of the powder charge. This greatly speeds up the inspection process!