I'm a noob here and wanted to know what chrome moly is and where it was originated.  I was looking in the cleaning and maintenance section of the forum and stumbled across a website that had some type of moly extreme coating you could put in your barrels to keep it form collecting carbon, copper, and other foulings.  Some barrels come with a "chrome-moly" barrel.  Is this the same thing as the moly extreme?  Do chrome moly barrels help prevent dirty barrels as much as the moly extreme stuff?  Enlighten please, and thanks!

Hate to break it to you but all barrels are chrome-moly either 4140 or 4150, unless they are stainless steel



What I think you are referring to is chrome lining, which is hard chrome, not like chrome plating on your cars bumber



http://cheaperthandirt.com/blog/?p=2678



Read above link for more info



 

Chrome moly alloyed steels have been around since early last century.  I think I read once that Bethlehem Steel in Pittsburg, PA may have been the first mill to formulate the chromium/molybdenum recipe with varying percentages of carbon to increase strength of the parent material.  The content of the steel alloy has basically no effect on how a barrel made from it will foul during firing.  Powdered molybdenum coated bullets do tend to foul any kind barrel less than uncoated bullets.

I think it's likely you are talking about two completely different things which happen to have part of a name in common.

The "moly extreme" you mention is likely molybdenum disulfide powder, which is applied loose to bullets and bores mostly in benchrest or other high precision shooting.  Some swear by the practice others swear at it.  It's not something most everyday shooters need to worry about.

"Chrome moly" is just a shorthand description of a type of steel alloy, which is what most rifle barrels are made from.  Not to be confused with "chrome lined" which is a thin layer of chrome electroplated onto the bore of the barrel.

Very good description above matching my research and previous industry (non-firearm) experiance.

Related Question:  what makes for a more accurate barrel:  standard Chrome Moly or Stainless Steel?  I'm going to be buying a new upper soon for a Coyote/predator gun and need to decide on the barrel steel.   I know SS has improved corrosion resistance but what else?  Does it machine to better tolerance also?

Related Question: what makes for a more accurate barrel: standard Chrome Moly or Stainless Steel? I'm going to be buying a new upper soon for a Coyote/predator gun and need to decide on the barrel steel. I know SS has improved corrosion resistance but what else? Does it machine to better tolerance also?

You can also get it melinite coated inside and out, it's harder than chrome and doesn't add thickness to the barrel like chrome.

Yes I think this pretty much answers my questions about it.  The stuff I'm talking about is Moly FUSION from the Shooter Solutions web site.  They advertise this stuff you can buy to put down your barrel to make it virtually friction resistant.  They go into trying to explain what it does through a bunch of scientific chemical jargon that is enough to convince me not to even consider trying it.  I'm not sure if this stuff is widely used but I can tell you their many warnings and disclaimers should pretty much scare anyone away from putting it down their barrels.

Here is a link http://www.shootersolutions.com/index.html

barrel steel has nothing to do with the accuracy potential.  what you are referring to is whether or not it is chromelined.  

the chrome lining process typically goes like this -

a barrel is made and the bore is cut
the barrel is acid etched to open up the bore a bit
the chromelining is applied to line it and make up for that bit that was etched away

the acid etching process is what degrades accuracy by creating variances in the bore and inconsistencies

one maybe two companies make the bores oversized to begin with in order to counteract the need for the etching process... LMT comes to mind.

SS is not chromelined so it never gets the etching process.  

this is pretty well a moot point for the most part unless you are capable of shooting better than a chrome lined barrel can shoot, are using expensive quality ammo that will produce the maximum results and are shooting in a style which would give you the maximum results.  

your best bet is to get whatever the hell you want and shoot the hell out of it until you are capable of actually knowing and deciding what YOU need.  

That's not loose powder but sounds like some kind of surface chemical treatment to adhere molybdenum disulfide to the surface.  Not impressed with that webpage at all.

As a self confessed "noob", I'll offer the advice that you're making a mountain out of a molehill.  Most of this kind of stuff (like that moly treatment) is only useful for a small number of people in precision shooting disciplines, not the everyday shooter.

If you're looking to get into precision shooting, whether competitively or not, you have a lot of stuff to learn and practice that's way more important than that first.  If you're interested in general shooting at a range, hunting, personal defense, etc, don't worry about it either.


Traditionally, stainless was the choice for most high-precision barrels because of its characteristics of being a softer steel which was easy to machine to precise dimensions with a very smooth finish.  Traditional stainless alloys though are not very heat resistant or as strong, so are usually limited to heavier profiles or else risk drastic reduction in barrel life.

Cutting tools and technology has advanced somewhat to where today a barrel of a much stronger and more heat resistant steel like the chrome moly or chrome moly vanadium alloys can be made to virtually the same level of precision.

Traditionally, non-stainless steel barrels had the disadvantage of either being subject to corrosion without careful attention, or lined with chrome or other material to protect against corrosion which would tend to degrade accuracy for precision barrels.  Gaining in popularity nowadays is the use of nitrocarburizing (aka nitride) treatments for CM/CMV steels which do not change the surface dimensions as chrome lining does, yet provides a hard, wear and corrosion resistant surface.

read this http://www.ar15.com/content/page.html?id=493