I know all the differences between Chrome lined and not and im not trying to start that flame war up, but how do all these Chrome Moly barrels and Stainless Steel barrels compare.  From what I can tell they are used for ultra accurate heavy barrels and last somewhere between chromed and not in number of rounds.  

If the material lasts a good while and is good for heavy accurate barrels, what would be wrong with having one turned down for a accurate lightweight barrel?

Also are they heavier than regular 4140 and 4150 for the same diameter barrel?

If turned to the same specs, there is virtually no difference in weight between a stainless and chromemoly barrel, lined or unlined.  You can get barrels of more conventional non-bull contours from Olympic Arms.  Unless fired extensively in full auto, really cooking the barrel, you will have good barrel life from a stainless, and few corrosion worries.

So would a lightweight contour on a Stainless or Chrome Moly barrel be more accurate than the same contour on a 4150 chrome barrel or even non chromed barrel? Im talking about making pencil barrels if it makes a difference.

I would seriously any human shooter could tell a difference in accuracy due to material of the barrel.  A pencil barrel is not intended to be a tack driver anyway.  Where the SS barrels excel are due to ability to smoothly machine a bull target barrel, and for regular contour barrels, their use in high humidity or marine environments, a rifle stored on your boat, trunk of a LEO's car, coastal areas, or a firearm put away for long term storage.'

I think most would agree a chrome-lined barrel will take more abusive use.  Many credit the chrome in the chamber for being more slippery and allowing easier extraction with some ammo.  (My stainless and chrome-moly barrels have not had any extraction problems, so I don't see what having chrome could improve on.)

It is certainly easier to find chrome-lined barrels in the pencil contour than stainless.  If your goal is to build a lightweight corrosion resistant rifle, you might consider buying a chromelined barrel, and having the entire rifle Robar'd or Black T'd.  

On the other hand, if you are hoping to gain heavy barrel target accuracy from a pencil barrel by going stainless, I think you will be disappointed.  But I also think for practical shooting, a pencil contour barrel will do fine if you are not looking for bench rest accuracy.

Thanks. Thats exactly what I needed to hear. I dont know much about anything other than 4140/4150 steel. Thanks for filling me in.