Moly Coated Bullets

In recent years there have been many claims that coating a bullet with molybdenum disulfide increases velocity and improves long-range accuracy. Without question, a thin layer of "moly" makes the bullet slicker, reducing friction as it travels down a bore. As an added benefit, the bullet slighdy coats the bore, leaving it cleaner and somewhat impervious to powder fouling, and thus easier to maintain.

Whether applied as a liquid that dries into a film coating or impact plating using a tumbler and wax sealant, this moly coat is so thin that it doesn't change a bullet's outer dimensions.

Before his untimely death, I spoke with NECO founder Roger Johnston, who developed the impact plating process, the most-used means for moly-coating bullets. When done in combination with BlackStar barrel treatment (see Chapter 2), Johnston reported that moly-coated bullets yield a 13 percent decrease in chamber pressure but only a 3 percent decrease in velocity, suggesting that the powder load could be modified to yield much flatter trajectory without exceeding a rifle's maximum chamber pressure. That offers remarkable ballistic possibilities that have yet to be fully realized.

There's no question that moly-coated bullets help a bore better withstand powder and copper fouling. Black Hills Ammo owner Jeff Hoffman, a competitive shooter and former SWAT sniper, used to clean his bore every 20 rounds. But now, he reports, "I shoot all day long, typically 80 to 100 rounds, then clean at the end of the day. Cleaning is easier than before, even after [firing] four to five times as many rounds." Hoffman's company offers America's widest variety of loaded, moly-coated match ammo, some 14 high-quality loads in .308, .223, and .300 Winchester Magnum.

Walt Berger—a longtime champion rifleman and president of Berger Bullets—is also convinced of moly-coating's efficiency. "I have shot 1,193 rounds of moly-coated bullets," he says, "without having to use a bore brush once—and a high of 73 rounds before using a patch saturated with solvent." Berger now moly-coats a variety of his commercial match bullets.

While developing the Ml 18 Long Range round, the Lake City Army Ammunition Plant included several tests using moly-coated bullets, which "all shot better than control cartridges in 600-yard accuracy tests." Interestingly, these loads also demonstrated a "measurable reduction of chamber pressures." However, by the time the distance reached 1,000 yards, the moly-coated rounds performed no more accurately than other loads. Had these test rounds been loaded to higher velocity—which the reduccd chamber pressure could allow— they may have scorcd better at 1,000 yards, too.

One long-range shooter who boosted his powder load to exploit that reduction in chamber pressure claims a phenomenal 5 MOA reduction in bullet drop at 1,000 yards. Another reports a marked improvement in shot-string consistency—that is, unable to clean his rifle every 5 or 10 rounds, he nonetheless finds consistent accuracy from his 15th or 20th or 25th rounds due to less bore fouling, so his bullets impact consistently. Previously he'd found his groups open up after about 10 rounds.

I don't think there's any question that moly-coated bullets have a beneficial impact on longrange shooting accuracy. But clearly defining, measuring, and standardizing that impact, and understanding the dynamics of how it all fits with powder load and rifling and resulting velocities, is still something of the future, which perhaps we'll see reflected in the next generation of sniper ammunition.

Beyond any doubt, the .308 Winchester (7.62mm NATO) is the world's most popular military and law enforcement sniping cartridge, and for good reason.

This bullet is powerful enough to penetrate most media a police or military sniper would encounter, yet it's not a heavy magnum round that generates punishing recoil. And it packs sufficient lethality for even the most drug-crazed suspect with one well-placed shot.

Unfortunately, by contrast I know of several stateside police sniping engagements in which

An abundance of ammo—all .308 Winchester 168-grain 8THP Match.

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