Moly Coating - Salazar

This is the fourth in a short series of articles about moly-coating. The series covers technical and practical aspects of moly-coating. This article describes my coating process. If you are interested in moly-coating, I strongly recommend the NECO process and materials.

I've added an update at the bottom describing WHY I use moly-coated bullets.  01-03-10.  -GAS-

Moly-Coating Process - Step by Step
by Germán A. Salazar

My moly-coating procedure largely follows the process set forth by NECO in the instructions. I hesitate to deviate too much from those instructions because I believe that Roger Johnston and Merrill Martin, who developed and patented the process, knew what they were doing, tried a lot of different approaches and determined that this was the best. I would rather follow the process that try to reinvent it. For those of you who are interested, the patents are available online; I use the Google patent search for my limited patent research.

For the sake of clarity, I will break the process down into numbered steps and will provide photos where appropriate. All photos may be clicked to enlarge.

1. Clean the bullets. Generally speaking, bullets need to be cleaned prior to moly-coating. While there are some brands, notably Berger, that are clean right out of the box, the cleaning process is fast, simple and harmless so there is no sense in skipping it. I often read descriptions of bullet cleaning for moly-coating which involve all sorts of powerful chemicals, most of which are hazardous to humans to a greater or lesser extent. This infatuation with harsh solvents is completely unnecessary! There is nothing like good old soap and water to clean bullets. Most of the dirt on bullets is a combination of dust, finger oils and light residue of bullet making lubricant; all of these are easily removed by a good dishwashing soap and water (the universal solvent). Once in a while you may have a batch of bullets from a custom maker that still have all of the bullet making lube on them; in this case, simply tumble the bullets in corn cob for 20 minutes or so prior to washing.

I wash the bullets under warm water with the dish soap; it gets a lot sudsier than the photo shows once you start to agitate the bullets with your fingers.  Get them nice and clean.  Once they're done, I rinse them thoroughly, drop them on a clean towel, run them back and forth and set them in the sun for a few minutes while I get the moly drum ready. I don’t want to see any visible drops of water on the bullets when they go into the tumbler, but I don’t worry about water droplets too small to be readily seen. A bit of moisture won’t hurt the process.

2. Heat. The biggest thing I’ve learned over 13 years of moly-coating is that the process works best when everything is hot - real hot. Since our daytime temperature in the Arizona desert exceeds 105 degrees most days for a period of six to eight months, finding heat is not usually a problem. I set the drums out in the sun at least 30 minutes prior beginning the process and by the time I’m ready to put the bullets into the moly drum, the temperature inside the drum is well over 100 degrees. I leave the drums and tumbler in the sun for the entire process. If you are in cooler weather, do whatever you can to maintain some heat in the drum - expose it to sunlight or some other source of heat during the process. Simply heating the bullets with a hair dryer prior to putting them into a cold drum isn’t effective.  These pictures were taken on an 85 degree day so don't think that extreme heat is required.

3. Ratios and Time. I use a full jar of the NECO provided steel shot in each of the two drums. I typically tumble 100 bullets in the 190 grain range, 150 bullets in the 155 grain range or 200 in the 105 grain range. These quantities allow the tumbler to turn properly without bogging down and also allow the process to take place in a reasonable amount of time. The amount of moly per load is relatively small as show in the photo - the amount shown weighs 5 grains and will coat the quantities described in 45 minutes.  These pictures show the process for a load of 150 Sierra .308, 155gr. bullets.

The actual time required to get a good coating on the bullets will vary depending on the temperature, the amount of moly used and the number of bullets in the drum. However, for the ratios mentioned above, on a hot day, I find that a perfect coating can be applied in 45 to 60 minutes of tumbling.  Note that the next batch of cleaned bullets is sitting out getting hot while the first batch tumbles.  The batch shown in these pictures tumbled for 50 minutes.

4. First Cleanup. Once the bullets are coated, I pour the bullets and shot into a soft towel and separate the shot from the bullets.  I use a Radio Shack video tape eraser (really a large electro-magnet) to separate the shot from the bullets. It’s very handy but with the demise of video tapes, I don’t know if they still sell these. Maybe eBay will be a source for one.  Once the shot is separated, I roll the bullets back and forth in the towel about 20 times. This leaves them looking perfect, but the process isn't over.

5. Wax. The principal differences between the moly step and the wax step are the amount of wax used and the length of time in the tumbler – both are greatly reduced for the wax. The photo shows the amount of wax I use and it is only put into the drum on every second load. The time in the drum is 75 to 90 seconds. Heat is just as important to this step as it is to the moly step - maybe more.  If excessive wax is used or if they are waxed too long, the bullets will have dark spots on them and feel a bit lumpy.  Just roll them  in the towel until they feel smooth if this happens.

6.  Second Cleanup.  After the wax coating, I once again separate the shot with the electr-magnet and roll the bullets back and forth a few times in the same towel as I used for the moly step.

That’s it! You should now have good looking, evenly coated bullets, providing 100% of the benefits of the process as patented by Merrill Martin and proven in competition by Norma, David Tubb, Berger Bullets and many others.

UPDATE - Why I Use Moly-Coated Bullets  Jan. 3, 2010

I use moly bullets in everything I shoot, however, what I shoot is typically relatively long bullets for their caliber, like a 190 in .30 cal. or 105/115 in 6mm.

That is an important point, because I think moly got a bad name because it was oversold as a cure-all when it really is just a lubricant. Cleaning methods and frequenct don't change with moly and barrel life is largely unaffected as far as I can tell. However, because in Highpower we shoot about 70 shots in a prone match and there is no opportunity to clean the rifle, fouling, especially jacket fouling, can be a concern. When you get to the last string of 20 shots and the barrel is fouled, your chances of shooting the winning score are slim. As a perfect example, in yesterday's match the winner shot a 600-34X, second place was 598-44X and third (me) was 598-41X. I was trying to overcome the second place finisher who shot on the relay ahead of me so I knew his aggregate and I also knew I would have to fire a 200-17X on the last string to beat him. He had fired a 200-18X on his last one, I was at 398-28X before shooting my last. I shot a 200-13X so I didn't get past him, but it wasn't any fault of the rifle or load, I just didn't get the wind perfectly as I would have had to in order to move up. I bring out all this just to indicate the importance in Highpower of being able to have peak accuracy all the way through the day.

Now, back to long bullets, they obviously will tend to jacket foul more than short bullets as their bearing surface is longer, and the fast twist barrels they require makes it worse.

Moly reduces the severity jacket fouling - it won't eliminate it. But, it reduces it enough that I find accuracy unimpaired through the day, something that isn't the case with bare bullets. I compile the scores for all of our matches as the club statistician and so I get a nice look at everyone's progression on a given day. As it turns out, I also know who shoots moly and who doesn't among the top shooters. It's usually fairly clear, by watching the X count, that the bare bullet shooters suffer a small decline in accuracy at the end of the day - I don't. That 200-18X that I mentioned earlier, was by a moly shooter, by the way.

In Benchrest shooting, with short bearing surface bullets, slow twists and frequent cleaning, I don't know if the benefit would exist at all. Having never competed in a Benchrest match, I really can't say. However, I speak to Lester Bruno several times a week and we discuss all these topics and he is no fan of moly although he tends to repeat the old wives tales about barrel corrosion, etc. more than any real testing of his own. I borescope my barrels after each shooting session and cleaning, I can tell you there is nothing in there but bare steel. I clean with Shooters Choice, Kroil and IOSSO paste, no brushes, and the barrels clean up just fine. The only thing I do a bit differently is that I'm in no hurry, I let them soak for days, just running a fresh wet patch through every few hours or morning and evening if I'm at work.

Update - July 5, 2010.  The photo below is the last target fired on July 3, 2010 during some bullet testing at 100 yards.  This 10 shot group was fired after over 100 rounds had already been fired through the barrel.  It was shot prone, with iron sights.  This is the kind of thing I mean when I say groups at the end of a lon day of shooting are as good as they were at the beginning.  All bullets fired that day were long, heavy, 30 caliber bullets, from 180 to 200 grains.  The barrel, which has over 2000 rounds fired (.30-06) cleaned up nicely with only light copper fouling.


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