Number of rounds to fire-coat a bore with moly?

[eric32]

need some advice

I will be making the switch over to MOLY coated 190 SMK in order to improve accuracy over a 20 shot strings for F-T/R matches for my 308win rifle. I have been scrubbing down the bore all morning to as clean as i can get it. I have a small stash of H4350 that i will try and use for coating the bore with the first moly bullets.

But I don't know how many rounds to shoot in order to coat a 28" barrel, I have used google in order to get some ideas but the research has yielded some very vague answers. Some people say 10 rounds and some say 30 rounds. And the info that I gather some of things that where said it seems right so I discarded the information.

Planing on using these components

Winchester Brass
CCI 200/BR2/ Win LR
IMR 4064
190 SMK and when i get some moly in, i will coat my 208 amaxes.
Plan on soft seating, OAL will be about 2.90 give or take

 

[eric32]

Did you prep the bore before hand?

 

[eric32]

ok thank you very much, i have just read so much stuff about prepping the bore before shooting. And it taking 20-30 rounds down the tube to get it conditioned before accuracy and speed levels off.

 

[tenring]

First of all, moly coating bullets will not improve accuracy. The expected result is longer barrel life. After coating, you will need to experiment with loads, usually increasing powder to achieve same results as with naked bullets.

I coat .224 Bergers for 500 M competition. Starting with a switchy clean barrel, it takes about 15 - 20 shots for my barrel to settle down and return to its accuracy node. I have tried pre shot moly coating swabs in the barrel beforehand but they don't seem to help much.

 

[Shynloco]

First of all, moly coating bullets will not improve accuracy. The expected result is longer barrel life. After coating, you will need to experiment with loads, usually increasing powder to achieve same results as with naked bullets.

Purely out of curiosity and since I haven't EVER shot a moly coated bullet out of any of my barrels (in more than 45 yrs+), other than extending barrel life, what is the benefit if shooting these bullets? Every time I see a post anywhere on moly coated bullets, I also see comments about the length of time it takes to clean a barrel thereafter and some have gone as far as saying you never get all the moly out. Not knocking it, just curious as to the measurable benefits of shooting these types of bullets. Thx guys.

Alex

 

[eric32]

i was under the impression with MOLY

1. it would foul a lot less and help with copper fouling. thus keep up accuracy for a longer period of time.

2.Along with less pressure allowing for a greater powder charge thus improving load density, thus improving ES.

 

[Shynloco]

Thx Eric. Now assuming those two issues are true and beneficial (not saying they aren't), then why isn't everybody's brother using Moly and especially in completion shooting of all types and disciplines? Thx again.

 

[eric32]

i haven't one clue but it wont kill me to try right?

i have a barrel tuner in my rifle so I frist do load development and try to get a really low ES for 20 rounds

then tune accuracy with the barrel tuner

 

[Shynloco]

Thx Eric. Don't think I'm pickin on you and by all means try whatever you think works best for you. And though I've heard your explanations before, I'd like to hear something even more conclusive to convince me to use moly's. It just strikes me that if there were more benefits than negatives, everybody would be using moly to get that "edge." But that isn't happening, manufactures produce far more "uncoated" bullets, and shooters buy mostly non-moly coated bullets and I'm curious as to why. There have got to be negatives that aren't being talked about with moly coated bullets and I find it difficult to believe that many shooter hate the ritual of cleaning a barrel as the sole reason why not to shoot moly's. Thx again.

Alex

 

[NCVarhtr]

I've been using Moly for close to 20 years. Lots of information out there that is not necessarily absolutely correct. It will help reduce fouling. It will enable you to fire a lot more rounds without losing accuracy. I have found that I get the very best results by cleaning right down to bare metal.....Once your barrel is completely clean, I like to coat it with Moly paste. Leave it a while, maybe over night. then start shooting. Usually 3 or 4 rounds and your barrel is ready....

 

[eric32]

NCVarhtr,

1.After how many rounds do you clean down to bare metal?

2.What cleaning Solution do you use to accomplish this goal?

3.What brand of moly is the preferred one?

Shynloco,

I do not feel like you are picking on me you asked a very good question, but i am not trying to convince anyone one in the MOLY vs Un-Coated bullet war. I am doing it due to it's ability to reduced pressure so i can get a fuller case of powder to try and cut my ES and SD to what i hope are the single digits.

 

[treeman]

there are two negatives to using moly. one is they are messy and two it draws moisture i.e. it is hygroscopic. i ruined a good chromemoly barrel leaving it in there too long. I used it for about 10 years and it does seem to extend barrel life an lessen copper fouling. I plan on starting to use hexagonal boron nitride. it is reported to put a first cold dirty bore shot into the group. I guess I'll find out. If you do use moly oil the bore after shooting if you aren't going to clean and run a couple of dry patches through it before shooting again
cheers

 

[jonbearman]

alot of moly users went to tungsten disulfide I believe and then to hbn (hexagonal boron nitride) to get away from the mess mostly.The hbn is super slick and you treat the barrel with alittle hbn suspended in 91 percent alcohol and swap the barrel and let it dry.It gets in the microscopic pores and stays there supposedly.I am going to try coating soon to try the hbn.I have used moly for 10 plus years with no problems and it cleans out pretty easy for me.The downfall with moly is it attracts moisture so you should lightly oil the bore to prevent rust from storage as you normally do anyways.When cleaning with moly I discovered that copper was almost non existent in the barrels I have.

 

[eric32]

The reason moly is appealing to me right now is my discover the WET application method of moly. Using water and a bottle and a tumbler

 

[swed6.5]

I used moly in 1 barrel, end result ,a naket bullet works better for me. The main thing to worry about and is true. if shooting over a chrony you will know when your barrel is fouled your speed will slow and stabilize. Know if you are pushing your load on the hot side and decide to clean your barrel after using. now your next load of previously borderline hot loads are now going to peak to a new high until the barrel is re fouled. when you show up to a timed match and need to refoul a clean barrel and quickly rezero with your hotter more accurate load ,, well thats my point i was using more ammo and powder with moly than a typicle 2-5 sighters of naket bullets. i have a lot of moly coated bergers left for play now

 

[Shynloco]

To all, thanks for the information coupled with your reasons for using moly coated bullets. I had been aware of the less copper advantage of using moly and even some have told me previously of an increase in velocity when shooting over a chrony. And Donovan made reference to having a barrel that he used in competitions for moly bullets which suggests that he may be using specific barrels for specific shoots, i.e switching out barrels. And jonbearman makes mention of shooters using moly also using a certain formula for cleaning the barrels and perhaps one issue I was searching for, the downside of the moisture gathering issue which he explains can be overcome by the proper use of oil, I suspect for mostly storage purposes of a barrel. So thanks to all for a very enlightening explanation of an area that I've avoided, mostly because of the fact that I try very hard to keep my barrels clean and shooting well. Perhaps I'll try and dabble some with moly coated bullet, but might approach it as Donovan suggests with a dedicated barrel for moly coated bullet. Guess I'm too picky about adventuring into using one of my regular barrels that are increasingly more difficult to find and buy without having to wait 6 - 8 months to be made. But a great conversation by all. My thx to all for the education.

Alex