Moly coat bullets

[Frank Green]

Had a forum member ask me my opinion on moly coating bullets. I figured I would post my response here so everyone can see it. I know it's probably been beat to death before. Again my response is my opinion in some cases and from what I've seen over the years. I do get asked the question quite a bit over here. I feel it's a good read and if it helps guys in they're decision making I'd post it here as well.

Later, Frank
Bartlein Barrels

I personally don't shoot and never will shoot moly coated bullets. Why?

It's another variable and I say a huge variable to contend with if you have problems with the gun shooting.

Moly has been know to cause pitting/etching of the bore of the barrel. Doesn't matter if the barrel is s.s. or c.m. steel. What I feel happens is moisture gets trapped in with the moly and the sulfur etc....and if the barrel isn't cleaned in a timely manner you get a chemical reaction. Some guys say you can shoot longer strings of fire and don't have to clean the barrel as often etc....When I'm told this I ask the question...."How many rounds do you go in between cleanings/strings being fired?" Sometimes I will get answers like 60 rounds. My comeback is what are you gaining? My hi power match rifles (not killer magnums) like .223 Rem., .308 win., .284win., .260 Rem. type chambers etc...I expect my guns/barrels to hold accuracy and go 100+ rounds in between cleanings (this takes into account the barrel is in good shape and not at the end of it's life). My 6ppc benchrest rifle I've put over 100 rounds thru it with out cleaning. The last time I had it out my last five, five shot groups the gun averaged a .177" for 25 rounds being fired. The barrel had 105 rounds on it with no cleaning thru out the day. One of my groups at a 100 yards measured a .098" in those last five groups! So I don't see any gain from this point of view.

Most agree that you need to have X amount of rounds down the barrel with moly coated bullets before the barrel will settle down and group consistently to build the moly back up after cleaning the bore. So now I have to put 20 rounds or more down it before I can shoot it in a match/record string?

Also you typically lose a little velocity shooting moly. So guys have to up there loads to get the velocity back. What they don't understand is your pressure hasn't changed for the most part. So you up your loads and now you just upped the pressure on your ammo/gun. Every gun, chamber, loads will vary.

How this company vs. that company or worse yet from one individual vs. the next guy moly coats they're bullets is another variable. They don't all do it the same and or use different ingredients in the moly. This guy waxes his bullets and the next guy doesn't etc....

Moly does nothing for barrel life in my opinion and from what I've seen. Some say yes.....I say no. A real good friend of mine is a very good shooter and for years we shot hi power service rifle together. I call Dave (his real name) a technocrat! He reads all the fine print on instructions, keeps detailed notes on everything. Knows exact round count on his barrels, load data down to the lot of powder and bullets, primers etc...that he has fired thru them. He asked if he could bring in two of his service rifles in for me to take a look at the barrels (both were AR15's with our barrels on them). One rifle had exclusively been shot with moly coated bullets. He uses this gun for practice which was shot every Wed. night during the summer and used it in smaller type matches. He would only clean it like once a month. When he cleaned it the gun on average would have around 400 rounds on the barrel. The other gun was shot strictly with uncoated/naked bullets. Both guns had 6200 and 7400 rounds on each barrel. The gun with 7400 rounds on it was fired with the uncoated bullets. Same chamber reamer used on both barrels and both barrels out of the same lot of steel. The barrel with 7400 rounds on it had like .010" more throat wear but I expected this as it had more rounds on it then the moly coated barrel but the difference in wear to me was of no concern. Both rifles still held accuracy with no issues.

Accuracy is pretty much a wash between moly bullets and uncoated bullets.

I asked one of the bullet makers over here back when Moly was a rage and in high gear. Why do they offer moly coated bullets? What do they see? They said the same things I listed above. Then I asked why do you offer it then? They said at the time the market had a demand for it. Also they could charge an extra $1 per box of bullets. So they made more money as well. They don't offer moly bullets anymore as there is no demand for them. I won't say who the bullet maker was but I will say you guys either shoot they're bullets or have at one time or another.

So if there is no accuracy gain, no gain in barrel life and you still have to clean it and throw in the variables with possible bore damage, how the bullets are coated, possibly need more fouling shots to shoot moly coated bullets before the barrel will settle down and give repeatability in terms of accuracy. Why do it?

Like I said earlier. If I start having problems with the gun in terms of accuracy it's another variable I have to take out of the equation/look at. To me the less variables the less headaches!

Also Scott here at work has everything to moly coat bullets. Has 5 different types/grades of moly. Has waxed bullets, not waxed them etc....in some cases the guns shot worse but none shot better. He has the tumblers etc...everything to do moly coating. He says he will sell everything to you cheap if anybody is interested! He said he fell for the fad when it got big but won't moly coat anymore himself.

[Barry Davies]

That will open the proverbial can of worms, but could'nt agree more.
Been there, done that, gained nothing.
Good post Frank.

[ShaneG]

Hi Frank
Very insightful info there, thanks!
I have similar previous experience in using moly attempting to get longer intervals of barrel clean and velocity.
Used it for years in an old L46 Sako .222 Improved.
Found it could take 12-15 rounds to return to accuracy after cleaning.
Cleaning was difficult once fouled - sometimes looked like a black powder bore.
Accuracy went south at approx 80 rounds - would quadruple group size at that point.

A further query - have you had any experience with HBN coating - and if so your report on same?
I imagine it could be similar to moly?
Cheers
Shane