The Lee Auto Disc powder measure is a popular choice among reloaders for its affordability and ease of use. However, accurately setting it up requires understanding the accompanying chart and making adjustments to ensure consistent powder charges. This guide will walk you through interpreting the Lee Auto Disc powder measure chart and mastering the art of precise powder dispensing.
Understanding the Lee Auto Disc Powder Measure Chart
The chart itself isn't a single, universal document. Lee Precision provides charts specific to each powder type and disc size. These charts are crucial because they provide the relationship between the powder type, the disc used, and the resulting powder charge weight in grains. You'll find these charts either included with your powder measure, on the Lee Precision website (though you won't find downloadable versions here per your instructions), or within Lee's reloading manuals.
Key Elements of the Chart:
- Powder Type: The chart will list specific powders (e.g., IMR 4895, Varget, Unique). Using the wrong chart for your powder is a serious safety hazard. Always double-check that you're using the correct chart.
- Disc Number: This identifies the specific throw bar disc installed in your powder measure. Lee uses a numerical system (e.g., #10, #20, #30). Different discs throw different amounts of powder.
- Charge Weight (Grains): This is the crucial information—the amount of powder dispensed with a given disc and powder type. The chart will typically provide a range of charge weights achievable by adjusting the powder measure's settings.
Using the Chart for Accurate Powder Charges
- Identify your Powder and Disc: First, determine the exact powder type you're using and the disc number installed in your Lee Auto Disc.
- Consult the Correct Chart: Find the chart corresponding to your specific powder and disc.
- Determine your Desired Charge Weight: Consult your reloading manual for the appropriate charge weight for your specific cartridge and bullet combination.
- Locate the Charge Weight on the Chart: Find the desired charge weight on the chart. Note that you may need to adjust the measure to achieve the precise weight.
- Adjust the Powder Measure: The chart usually provides instructions on how to adjust the powder measure to achieve the desired charge weight. This typically involves turning an adjustment screw on the measure.
- Verify the Charge Weight: Always weigh several charges using a powder scale to verify accuracy before proceeding with a full reloading session. Any significant deviation indicates a need for further adjustment.
Troubleshooting Common Issues
- Inconsistent Powder Charges: This is often due to improper adjustment of the powder measure, static electricity affecting the powder flow, or clumping powder. Clean your measure regularly, use a powder funnel, and consider using a powder anti-static device.
- Charge Weight Outside the Chart Range: You might need a different disc to obtain your desired charge weight.
- Difficulty Finding the Right Chart: Check Lee Precision's website or contact their customer service.
Safety First: Always Double-Check Your Work
Reloading is inherently dangerous. Never skip any steps, and always double-check your work. Use a powder scale to verify every charge before loading it into a cartridge case. Improperly loaded ammunition can lead to serious injury or death. The information in this guide is for educational purposes only, and should not substitute proper training and adherence to safe reloading practices.
Conclusion
The Lee Auto Disc powder measure chart is a simple yet crucial tool for accurate reloading. By understanding how to interpret and use the chart properly, you can ensure safe and consistent powder charges for your ammunition. Remember, safety and precision are paramount in the reloading process.
