The RCBS MatchMaster electronic powder dispenser is the current top model from the reloading specialists from Oroville, California. The manufacturer promises a dispensing accuracy of 0.04 grains, which corresponds to 0.0026 grams or 2.6 milligrams, and a dispensing time of less than 20 seconds. This also describes the two most important criteria for an electronic powder dispenser: it should be as accurate as possible and it must be fast. Before we start checking the key data, it is worth taking a closer look at the functions of the MatchMaster.
The RCBS MatchMaster Powder Dispenser from the STROBL.CZ product range in use
As with all electronic dispensers, RCBS recommends warming up the MatchMaster to the respective temperatures at the loading location for about 20 minutes before use. This time can be used to precisely align the trickler with the integrated spirit level. To do this, the two leveling feet are adjusted until the air bubble comes to rest in the center of the circular bubble level. Depending on how far the feet are unscrewed, the device then stands on three or five contact points on the base. You should take the time to align it exactly, as the load cell can only work accurately if it is aligned correctly. After switching on, a countdown counts down from 9 to 0. Shortly thereafter, "stable" appears in the display, indicating that the scale is ready. Before actual dispensing, however, the MatchMaster should be calibrated with the two calibration weights supplied, weighing 20 and 50 grams. This process only takes about one minute, the display shows the individual steps.
The unit has two dispensing modes, "Standard" and "Match". In addition, there are four different dispense speeds in each case. The manufacturer recommends the low speeds for large to small extruded powders and the fast speeds for flaky and ball powders. In the operating instructions, RCBS gives the recommended dispense speeds 1 to 4 for 29 different powders, as well as the approximate weight of a single powder grain. This is already a very good presetting for a high dispensing accuracy. Due to the large number of powder geometries and flow properties, the optimum dispense speed must be determined in practical trials. If dispensing takes too long, the next higher speed can be selected. Too short a time usually results in overcharges, in which case the appropriate speed should be reduced. The accuracy is given by the manufacturer with +/- 0.1 grains in the standard mode and +/- 0.04 grains in the match mode, if the powder selection is set correctly.
Compared to other powder dispensers, the RCBS MatchMaster operates with two independently running powder dispensing tubes. The larger diameter tube takes over the fast output of the powder charge. The smaller tube has an 80 percent smaller cross-section and is responsible for fine dispensing. This is how remaining powder draining or emptying of the dispenser is carried out: in contrast to the previous RCBS Charge Master Combo model, the drain opening is no longer on the right, but on the underside of the unit. A supplied plastic straw is inserted into the drain hole and then the drain disk is turned. This opens a valve and the powder trickles out through the straw, ideally straight into the powder canister. The powder in the powder tubes is discharged by pressing the trickle button. As long as the drain is open, a signal tone sounds. Very useful: with the previous model, it happened that the powder filled into the powder reservoir immediately trickled out again, if one had forgotten to close the drain again. The MatchMaster can also be controlled via Bluetooth using a smartphone. The appropriate app is available for Apple and Android. With the app, the main functions can be controlled: powder dispensing, calibration, configurations and loading protocol.
Accuracy check using a calibrated laboratory balance from Sartorius
For the practical test, we used a total of five propellants with different geometries. For each powder and setting, 20 dispensing processes were run through. In each case, the dispensing weight and the dispensing time were determined and documented, but more on this later. Sartorius Lab Instruments provided a highly accurate precision balance for checking the quantity of powder dispensed. The verified Entris-II BCE223I-1CEU model enables a resolution of 0.001 grams, or 0.0154 grains.
After calibrating the dispenser, the user must first set the dispensing speed. To do this, one of the digits between 1 and 4 is selected in the display and confirmed with the "Powder" key. Subsequently, it is possible to choose between match or standard mode. To do this, press the "Mode" key and select the "Match" menu item. Using the numeric keys 4 or 6, "on" can now be selected, the match mode is then shown in the display with "MAT", or when the standard mode is selected with "off", "STD" appears in the display. If this setting is not selected manually, the MatchMaster operates in the standard mode. In this mode the output weight is displayed with one decimal place, in the match mode the value is displayed to two decimal places with a resolution of 0.02 grains.
Now the desired powder weight is entered using the keypad. In the Auto mode, the unit starts tricking automatically, as soon as the load cell has settled down. In the manual mode, dispensing must be started pressing the "Go" key after the scale pan has been placed. Both feed tubes run together at the beginning. If a little over 95 percent of the target quantity is reached, only the small screw rotates for fine dispensing. A total of five different powders were measured, each with the standard and match modes, in 20 dispensing operations each. For this purpose, the time of each operation was determined; the display value, which indicates the amount of powder in the pan, was noted; and then the powder charge was counterweighed with the Sartorius precision balance.
Rottweil R901 is a short, extruded (rod-shaped) powder. The operating manual indicates the dispense speed 3 for this powder type. Based on the average of 20 loads, the MatchMaster requires 28 seconds in standard mode and 48.2 seconds in match mode. Therefore, the testers also tried the same powder in the highest speed setting 4. And lo and behold, the times could be halved with 14.1 seconds in Standard mode. In match mode, it even reduced by 30 seconds to 18.0 seconds. It was even possible to increase the accuracy with the exception of a single value. So it's worth taking your time to get to grips with the device and its functions. As already mentioned at the beginning, the powder drain on the MatchMaster is located on the underside. To do this, either place it over the edge of the table until the drain is free, or lift the unit up and then open. In both cases, however, the unit must be moved. If one wants to continue working with another powder afterwards, it is necessary to realign the Matchmaster after draining, if the base is not one hundred percent level. This was solved much more user-friendly with the side drain of the previous model.
Our conclusion about the fully automatic RCBS MatchMaster Powder Dispenser from STROBL.CZ catalog
The RCBS MatchMaster works with high precision. Exactly this point was not always given with previous models from RCBS and other manufacturers. Also, these devices allowed themselves dispensing times of not infrequently one minute and more per charge. The MatchMaster manages this in standard mode and with the correctly selected dispense speed in under 20 seconds. It takes somewhat longer in the higher-resolution match mode. The device offers very extensive setting options and can also be operated with a smartphone for technology freaks. If this is worth 1,439.16 euros, you will have a lot of fun with the RCBS MatchMaster.
The MatchMaster Powder Dispenser from RCBS is available at STROBL.CZ.
The Sartorius Entris-II precision balance came from Waagen-Kissling GmbH and is manufactured by https://www.sartorius.com/en.
