Originally Posted by kuntreebouy
i was just curious about it, I had never really thought about it until a guy I know built a AR and put a noveske polygonal barrel on it and was talking about how great it was for basically life expectancy of the barrel, after he went on and on and on,,,,, and did I mention he went on about the barrel and how great it was, I started wondering what the real truth behind it was and if it would make the accuracy better or worse, why the cost was so high, etc. after looking on the innerweb about it I couldn't really find anything about the accuracy of them, just that high dolla manufactures used them on there guns and the production of the barrels themselves were more costly due to million dolla hammer forging machines,, and personally I prefer accuracy over anything myself, hopefully ill be able to answer questions in the gunsmithing forum with you guys before to terribly long, I have always loved tearing guns down and tinkering with them and plan on taking a gunsmithing course after I get xmas done and paid for and the new year kicks in, thnx for all the comments on the question guys
The real truth behind barrels is that heat and/or cryo treatments are critical, 4150 may make a difference for full auto but means nothing to a target shooter.
The ammunition, chamber, muzzle, and plumb face of the bolt have more to do with accuracy than any type of rifling ever will.
ALL barrels, whether land/groove or polygonal wear out faster in the throat and muzzle faster than the rifling does, the throat because of the miniature explosion that the barrel contains (very hot) and the muzzle because of gas cutting and damage from careless use.
Yes, the engraving process wears out the rifling with use and higher pressure, higher velocity cartridges wear out the rifling faster.
The types of things you'd do to an AR to make it more accurate are pretty much the same things you'd do to any other rifle. Make sure the mating faces between the parts are perfectly plumb, decrease tolerances between those components, make the barrel more rigid by adding mass to it (contrary to all popular belief you can't make something more rigid by removing material from it in a "special" way but you can increase its surface area for slightly faster cooling), make sure the muzzle crown is as close to perfect as it can be, decrease lock time, and make the trigger as smooth and crisp as it can be. Oddly enough, in semi-auto rifles recoil spring quality makes a difference (not night and day, but there is a difference), too.
Basically, build quality and ammunition quality have a lot more to do with accuracy than special rifling. It may be that Noveske build quality and barrel tolerances are exceptional, which would indicate why it is more accurate and/or consistent than other rifles with general production quality components, machining, and fitment of parts.
In short, there's nothing special about the rifling but if your shooter friend wants to believe that, then