I've read enough about moly lube to know that I don't want to use it, but there is a question I have about something that I've seen several times on other sites/forums.

It goes: If you use moly you can expect a 50 ft/sec drop in velocity, the reason being that because of the slick lube, the bullet doesn't stay long enough in the barrel to build up full velocity.

It goes on to say that if you want to go back to regular bullets/lube you have to clean the moly out of the barrel.

Is it just me or is this real hokum?? If the bullet is moving faster and gets out of the barrel before the pressure peak, it is already going faster than it was before. Right?.

Physics, how does it work?



Yep, I believe that is hokum

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ΜΟΛΩΝ ΛΑΒΕ

I'll never trust the internet again.

Moly was the big craze, snake oil a few years back. I do not know about the speed reduction or increase, but do know that it is tenacious stuff. It is very difficult to remove from a barrel. It is one of the slipperiest stuff known to man.

If I recall the only way to remove it completely from a barrel is a lot of elbow grease and JB Bore Paste.

The fad seems to have faded away. There are still some moly coated bullets around, I am referring to the moly bore treatments.

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Still Running Against the Wind

I picked up a bunch of moly coated Combined Technology rifle bullets a few years ago when they were discontinued and on close-out. I've never noticed any difficulty cleaning, but I use Bore Tech Moly Magic and JB Paste after shooting them.

There is evidence that leaving moly in the bore can damage it over time because some of the components turn acidic with moisture. Then again, moisture combining with regular carbon and powder fouling will also initiate rusting.

I haven't noticed any problem changing back and forth between coated and non-coated bullets and I am an accuracy nut.

I have shot a lot of moly, done bullet coating, and researched all I could before doing so. My experience is with long range rifles, as there is no real advantage with handguns.
The drop in velocity is due to a drop in pressure from reduced friction in the barrel. It's not about how long the bullet is in the barrel. It's about how much pressure builds behind the bullet. We had to load a half grain or so higher to get back the velocity we lost.
Some of the qualities of moly have been proven, such as the statement above, and some have not - such as claims of longer barrel life.
Moly was useful to one main group of shooters - the NRA Highpower competitors and somewhat with the benchrest crowd. It's usefulness was in the fact that copper will not foul over the top of moly in the barrel. An 80 round match could be fired without barrel cleaning, a HUGE advantage, and with a conditioned barrel, point of impact did not change over the course of a match.
Moly reacts with humidity in a barrel to create Sulphur compounds which are corrosive, but the problem is exxagerated. (The sulfer comes from the sulfide in molybdium-disulfide).
Moly is cleaned out with Kroil. The JB is used mostly at the throat where sometimes a "ring" of carbon builds up. (and this carbon ring buildup is normal, moly or no moly).
My cleaning regime was Kroil, then Shooters Choice, then sometimes JB. A clean barrel requires about 10 rounds or so to re-plate the bore before POI stabilizes. I also pre-treated my bore by burnishing it with Moly paste which helps speed up the bore conditioning.

The reason the "fad" faded is that Moly has been replaced by HbN -HexBoron Nitride which has no reactivity and has a higher temperature stability (combustion point). The HbN is used for the same purpose that Moly as used.
Those who swear by it have their legit reasons, and those who don't usually don't want the added hassle of shooting coated bullets in general.

When reloading match ammo, the neck has to be sized tighter to keep the same neck tension on the bullet - hassle #1.

Messy as hell to coat and wax bullets, clean black crud from barrels - hassle #2

Having to pre-condition the barrel to get POI stabilized- hassle #3.
It's a bad idea to shoot coated and uncoated bullets together for many reasons too lengthy to list here.

common sense states that if it don't stay in the barrel as long as the non treated control ... velocity had to increase to achieve that reduction in dwell time.

something of a more probable explanation might be related to the variable nature of powder burn rate.
the bullet can start out easier, thus the volume behind it is larger before the peak pressure is realized. The rate of acceleration is will decrease as will the overall operating pressure of the load resulting in a loss.

It was common to adjust the powder charge to compensate for the lower pressure. If the pressure is built back up to equal the non moly load, you then have a gain

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it just needs more voltage

I am going to try powdered Dilithium Crystals this will keep my barrels free of anti matter.

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Still Running Against the Wind

It has to be true if it's on the Internet

Where did you hear that?

The Internet

That's just silly. Why spend the money for Dilithium when the anti-matter can simply be scrubbed out with a brush made of Unobtainium.