Is it possible? The reason i ask, is that I've run accross a barrel (at a great price) brand new for $140.00. It's a M4 contour barrel at 10.5" in 4140 Chrome Moly steel. M4 feed ramps and a TRUE 5.56 NATO chamber....so all in all a great looking barrel and at a STEAL of a price....however its not chrome lined...barrel or chamber. is it possible to have done, and if so whats a median cost? thanks guys!

I'd be concerned with it being 4140 with no Melonite/CL.  How many rounds do you plan on putting through it?

To my knowledge...it takes a special plating set up that only most very large AR barrel manufacturers have. No other plating shop I have spoke with does it. AR barrel manufacturers plate the ID of the bore and chamber by the hundreds at a time. IF, big if,  you found a plater to do it he would likely NOT do only one barrel. Good luck! Just buy a chrome lined barrel and move on.

i am as well, thats why I'm wondering if it would be possible to have it CL'ed. I plan on doing quite a bit of shooting with it for sure.

No need to cross post in multiple forums

http://www.ar15.com/forums/t_3_4/644135_Chrom_lining_a_non_chrome_lined_barrel.html

i was afraid that would be the case, but it never hurts to ask right?
thanks a bunch for the input, i really appreciate it.
ive got a few CL barrel from BCM, Spikes, i just thought if i could get it done on the cheap it would be worth trying one out.

Shoot the crap out of it.  In the meantime, go buy yourself another one that's CL'ed.  Replace it when you wear this one out.  Cheapest way to go.

Chrome lining must occur very shortly after barrel production from what I have read.

Plating adds thickness to the surface.  A .224 barrel before plating will be smaller than that after plating.  Barrels headed for the plater are slightly larger than .224 so that by the time they are plated they are to the .224 diameter. That was what did Kotronics in.  Their plater plated too thick and many of their barrels had pressure problems and he had to replace them.  While that would not be a big deal for a large company, for a small company like Kotronics (Cardinal) it was the beginning of the end.
Plate a .224 barrel and you can look at having a lot of pressure problems more than likely.
Just shoot the barrel you have, and when you wear it out replace it with a CL barrel.  Most likely you will not have to worry about it in your lifetime.

Just shoot it.  It will probably last a lifetime.  CL barrels are really becoming obsolete.  The process degrades accuracy.  Hot salt bath nitride treatment is superior to CL.  It is sometimes called by one of its brand names, Melonite. It is harder and more durable than chrome and does not degrade accuracy because it is not a potentially unevenly applied coating.  It is a hardening of the barrel steel, itself, both inside and out, at the molecular level.  It can be applied to your barrel, unlike chrome. But for civilian use your regular 4140 barrel will probably last you a lifetime.  You'll never see a CL barrel on a precision rifle if the competition rules give an option.  They will all be stainless, nitride, or 4140 steel.