Reloading, bullet to case contact

Reloading ammunition isn’t hard. Even reloading good, accurate ammunition isn’t hard, so much as painstaking.

One aspect of reloading that isn’t part of mainstream reloading practices, is adding a substance into the case neck. The standard wisdom is that you don’t need to do this step, and the standard wisdom is quite correct for standard uses of ammunition. There are two reasons to do it, weatherproofing the ammo, and trying to increase accuracy.

The military routinely does this with asphaltum as a neck sealer. Over the years competitive shooters using military ammo found they could get more consistent muzzle velocities by running the sealed ammo through a seater die to push the bullet back into the case a tad to break the asphaltum seal. I would argue that by running all that ammo through a resizing die to “break the seal” the competitive shooter also tightened up the bullet jump distance to make it much more uniform than arsenal grade ammo can produce, so whether “breaking the seal” or making COAL more consistent is the real lesson here, I can’t say with any certainty.

The next reason, to increase accuracy is a bit of a newcomer to the field of precision reloading. A product used to be on the market called “Froggy’s Neck Lube” which was supposed to be applied to the inner surface of case necks to provide a dry lube film. In theory this would uniform the amount of force needed to unseat the bullet. The case to bullet friction problem is real, as polished brass and polished gilding metal (the bullet jacket allow) have issues with friction. Adding a dry lube between the two would even out the force needed to overcome the friction, and make brass that was on the more polished end perform similarly to brass that was a tad rougher. That’s the theory, and if the groups shot by Froggy are any indicator, it certainly doesn’t hurt accuracy potential at all.

Now that I’ve addressed adding things to the case neck, I’m going to address the much more common practice of coating the bullet. Lubalox, Molybdenum Disulfide, Tungsten Disulfide, Hexagonal Boron Nitride, are the common lubes, and each has their own set of fans and detractors.

https://wanderingthroughthenight.wordpress.com/2016/02/01/hexa-boron-nitride/ What I wrote here is still true, accuracy gains are inconsistent. But since others have done testing, reviewing their results won’t hurt.
https://www.longrangeshootersofutah.com/boron-testing/ (nothing wrong with this article except the author not understanding that solid to solid friction reduction works on a different principle than aerodynamic resistance, so coating your bullets won’t make them more slippery through the air).

Still, plenty of top competitors coat their bullets and see improvements through their custom built rifles. Odds are good that a factory stick isn’t going to see a statistical increase or decrease in accuracy, there’s just too much noise in the data.

So, why would someone coat the inside neck of their brass with a dry lube and see an increase in accuracy when coating the bullet which provides the same dry lube benefit doesn’t? Well, there might be a couple reasons for this…if you don’t properly burnish the inside chamfer of your brass, the brass can actually shave off a bit of the bullet jacket when seating the bullet. Another would be that lubing the case neck doesn’t cause a buildup of lube in the barrel. Another could be it really doesn’t have any benefit over coated bullets and just happens to let some people shoot naked bullets more consistently.

Sometimes the “science” of reloading runs hard into the wall of “art” and you are left scratching your head.

So, what do I like? Well I like naked bullets and sealed necks in ammunition that I store for a long time. Any time I can buy pulled brass with the tar still in the necks I leave the tar there and just load ’em up with an accuracy load. After all, once you get under a minute of accuracy with your handloads, you are problem if you miss the X ring on the High Power line. For reloads, so far I haven’t bothered to lube the necks, but I’m considering it since my testing showed no accuracy improvement with moly, I might as well run the tests again with neck lube.

Unfortunately Froggy’s Neck Lube is no longer available for purchase, but rumor had it that it was just a colloidal suspension of graphite in alcohol. Even though I can’t find Froggy’s on the market, I suspect that a dry lock lube will give the same benefit, even if the liquid part of the colloid is now petroleum distillates instead of alcohol. As long as they evaporate off and leave the lube behind, you are good to go.

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