April 27, 2022Big Batch Case Lubrication Techniques — USAMU Reloading TipThe U.S. Army Marksmanship Unit regularly posts “how-to” articles to the USAMU Facebook page. The USAMU’s reloading experts looked into the topic of case lubrication a while back. The USAMU’s reloading team was responsible for loading thousands of rounds of ammunition for their team members. They have developed efficient methods for lubricating large numbers of cases. This article will discuss the USAMU’s innovative “big-batch” lubrication methods. You can also visit the USAMU Facebook Page for more helpful hand-loading tips. Today’s topic focuses on how to quickly apply spray lubricant to cartridge cases before they are sized. This shop typically orders 25,000 rounds. It is therefore possible to speed up the lubrication process. Although your ammunition loads are not as large, these efficient methods can help you save considerable time throughout your handloading career. Our case lubrication rates range between 1500-1600 cases an hour and 2400-2500 cases an hour depending on the caliber. This shop uses virgin brass while most home handloaders use fire brass. This requires some adjustments at times. These will be discussed as soon as they become available. Start with clean fired brass. To prevent damage from the decapping stem, this is a good time for you to clean out the case mouths with a tapered tool. You should shake the bin so that the cases face up. Next, take as many cases as you can with the mouths “up” from natural clusters. This is typically 3-4 for cases 7.62mm in size, while it can be as high as 8-10 for 5.56mm cases. Place the cases in the rack slots with the mouth-up. This saves a lot of time and is easier to do in groups than one. Once the clusters are empty, it’s time to shake the bin again to orient more cases “up”. This photo shows a USAMU employee making a case lubrication tray.
Adjust the spacing to best suit the calibers you are reloading. This size is convenient for handling the various phases of case oil/transfer to progressive feeders for processing. The 1/2-inch angle doesn’t cover the critical area at the base. This is just ahead of the extractor groove where the greatest re-sizing force will occur. USAMU uses virgin brass. Therefore, the amount of lubrication required for Full Length (FL), sizing of previously-fired brass is less than that required for our purposes. To avoid cases sticking to the full-length sizing device, use fired brass. To reduce expander ball drag, case stretching/headspace changes, and case neck drag, make sure you get some lube into your case mouths/necks. Spray lube used by this shop does not harm primers and powder and does not require tumbling to be removed after lubrication. Take a closer look at the image above. The rack can be easily rotated using a common kitchen turntable at USAMU. This rack is placed in a custom-made box to prevent over-spray from getting on floors and walls.
The following refinement of the above process speeds up processing of 5.56x45mm case is possible. A small cardboard box that holds 100 cases is fitted by a tape-sealed “floor”. The smaller 5.56mm cases can be picked up and arranged in a single pile. This saves time and allows them to be placed in the rack slots. This works well for our purposes: neck-sizing and setting neck tension for new brass. This procedure can be used with fired brass. Make sure you have enough lube to prevent any stuck cases. Good luck and happy shooting! *This test was performed in two parts. The first involved spraying heavily primed cases while getting more lube into their bodies/mouths than a careless handloader would apply. The second part involved literally spraying large amounts of the lube into the cases and then soaking the primers. After a few days, the primers were allowed to absorb the lube before they were fired in a test barrel. All were fired as normal. There were no unusual reports. All fired normally; no unusual reports were noted.
