A Guide to Reloading Powder Measures: From Basic to High-Tech

The powder charge is one of the more critical elements in reloading because it directly influences the muzzle velocity and chamber pressure, and the consistency of the charges dictates how consistently rounds perform. The methods by which powder charges are measured have not really changed, with them all being either volume or weight-based, but the equipment, the accuracy, and the consistency have certainly improved.

The Evolution of Lee Precision: From Auto-Disk to Pro Auto-Disk

Back in the 1980s, the Lee Precision Auto-Disk Powder Measure was the then state-of-the-art tool of choice. It came with a set of six disks, each holding six cavities of different sizes corresponding to different charge weights. Measuring charge ‘weights’ by volume is a very accurate and reliable method. The actual weight being discharged by this type of measure does need checking with a scale, but once you know the weight, you can rely on each cavity you are using to keep dropping that same charge pretty consistently. This was a basic tool, with a cast alloy body, and it relied on the underside of the plastic hopper to ‘cut’ the powder charge off as the disk passed under it. This friction led to wear after a few years, and other metal parts also started to rub on each other and stick.

The next step in the evolution of my own powder measuring was the Lee Precision Pro Auto-Disk Powder Measure. This is a more modern version of its predecessor, and it addressed several issues. The body is Teflon-coated, to ensure smoother operation, and an elastomer wiper cleanly wipes across the powder charge without friction or powder cutting. This version gives better and more consistent powder charges, operates more smoothly, and does not seem to wear.

“Hornady products are heavily built and incredibly durable, so they are a good choice, if not a bit more expensive.”

Micrometer-Adjustable Options: The Lee Perfect Powder Measures

In the 1990s, Lee introduced their Perfect Powder Measure, the first model to eliminate charge disks in favour of a single, adjustable cavity. The cavity is micrometer-adjusted, with a meaningful scale marked in cubic centimetres, and once set, it can be locked with a locking ring so it does not slip out of adjustment. When the measure is operated, the cavity is moved under the feed from the hopper and filled with powder. As the mechanism then rotates back, cutting off the powder supply from the hopper, it is moved to discharge powder into the case. This is a good design, giving consistent powder charges, and it is easily adjustable. To set it, you simply discharge powder, weigh it, and adjust the micrometre until you get the desired weight repeatedly.

Not a company to sit still, Lee Precision then introduced their Deluxe Perfect Powder Measure, which took the single-cavity powder measure up a good few notches. A precision die-cast body, a brass drum that is totally anti-static, a soft elastomer wiper, and a quick-change hopper with a powder cut-off were all introduced to make the tool smoother and better. A larger and easier-to-read micrometre was also added. A very heavy and stable stand was introduced at the same time, and it is well worth purchasing to support this tool.

Both of these micrometer-adjustable measures represent an improvement on the fixed-cavity designs.

A Hybrid Design: The Lee Deluxe Auto-Drum Powder Measure

The next powder measure to appear was the Lee Deluxe Auto-Drum Powder Measure, which combined features of the earlier tools. It used interchangeable drums, similar to the cavities in previous models, but each one was also adjustable, like the cavity on the micrometer-adjustable measures. The drums are adjusted with a small key, with approximately 1/10 of a grain increments, and, combined with a scale, setting them is a fairly quick process. If you label each drum with the powder type and weight they are set to, you can swap them over relatively easily, making calibre changes very swift.

This is a case-activated measure, like some of its predecessors, and it proved to be a real pain to set up on the press and get it to discharge powder consistently. Balancing how deep it sat in the expander die with the amount of movement needed to actuate the measure fully was difficult, and getting the measure to move through the full range of movement required without excessively belling out the case mouth took a long time. It went back in the box several times before I got it set up correctly. The latest version has a red anodised swivel adapter, and this may exist to alleviate this issue.

If you take the time to set this measure up as you want it, it is very good.

Heavy-Duty Precision: The Hornady Lock-N-Load Powder Measure

Hornady products are heavily built and incredibly durable, so they are a good choice, if not a bit more expensive. The Hornady Lock-N-Load Powder Measure is one such tool. It uses interchangeable and adjustable metering inserts, similar in principle to the metering drums on the Lee Deluxe Auto-Drum, but they are made of steel and incorporate a substantial and effective locking ring to prevent them from slipping out of adjustment. Features like a push-button release on the metering inserts, tolerances of 0.002”, and a powder baffle to regulate powder flow make this a very accurate and consistent powder measure.

The High-Tech Solution: The Hornady Auto Charge Pro Electronic Scale

Thanks entirely to the generosity of the team at Edgar Brothers, a Hornady Auto Charge Pro has been added to the reloading bench. This is an electronic, fully automated powder measure, which trickles powder extremely accurately into a powder pan on a scale. The speed and accuracy of the scale are fully controllable, and you can set and store charge weights in its memory. Having a scale to hand that automatically discharges a powder charge each time you put the pan onto it is really handy, and it does make the whole reloading process smoother and quicker. If affordable, this is a really good tool to have.

Conclusion: Choosing the Right Powder Measure for Your Needs

With the exception of the earliest Auto-Disk measure, all of these products are still available, and they all do a decent job of measuring powder. Wherever you choose to join the powder measure journey, be it based on cost, accuracy, or the speed of reloading you want to achieve, there is an option that will meet your needs.