Here is an interview w/John Noveske (link) http://www.defensereview.com/novesk...ecce-carbine-john-noveske-interview-part-one/
While I was in 7th SFG(A) and our C 3/7 (CIF) guys wanted a 10.5 goto barrel for their MK18s - they went with what John was producing..I will go a bit farther and say John is the kind of guy that knows his shit - read on:
Noveske: Here is the thing I hate doing, which is the used car sales pitch, o.k., ’cause I pretty much don’t really do it very often. But, what separates my product from the rest of the products out there, is…the obvious thing’s the barrel, and, from start to finish, the barrel goes through more inspection and testing than any other barrel out there that I’m aware of. From the point we pull the steel of the trailer in 12-foot bars, we instantly hardness test and serialize each bar. Then, every bar throughout the entire production process is numbered accordingly to its parent bar. And then, like I said, we designed all the tooling so the diameters on the drills, the bore reamers, the hand-lapping process, the button that does the button-rifling is our design, and it’s an improvement over conventional polygonal [rifling] in that you get an extended barrel life over conventional polygonal [rifling]. In fact, I’ve never heard of one of our new barrels shooting out. In a year and two months, there’s never been a report of one of my new buttons…the new types of rifling types [barrels] shooting out.
We designed that new rifling for our Extreme Duty Machine Gun Barrel Project for the M249 and the Mk46, and we had so much success with that new design that I quickly applied it to all of our M4/M16-type rifles. So, the new rifling is 1-in-7 twist. It appears, when you look down the barrel, as a 6-land-and-groove, and what we did was we adjusted the angles on the sides of the land to give us the optimal performance. After rifling, there’s a stress-relief process that is designed to pull out all the stress without losing any hardness. The barrels are then trued-up so that when we put ‘em in our CNC-contouring lathe, the contour is 100% concentric to the bore, so that you don’t have an strange harmonics when the bullet travels down the barrel, and that’s part of the process of…the contouring process is…I’m pretty protective of it, so that’s about all I want to say is that it’s very accurate.
And then, when we go to chambering, it’s a chambering process that I developed as an employee of Pac-Nor
, and I looked at how they were chambering barrels, and I saw the logic in it, and I found ways to improve it. The reamers are all custom-made for me as far as the grind, the angles, the number of flutes. The way we chamber, you never get any scoring on the lands forward of the throat like most other people have to deal with, because our chips are forced out the back. The end result is a beautiful, highly polished chamber. Every barrel is individually inspected to ensure against or prevent reamer wear and have an undersized chamber. They all get gauged on every point, and the design of the chamber is a design I developed after many different evolutions. This was designed to work…to do full-auto mag dumps with [Black Hills
] MK 262 Mod 1 [77gr Open-Tip Match (OTM) 5.56x45mm ammo], and now you can sit there and pour as much ammo as you can through the gun on full-auto, and the thing that’s gonna’ fail is the gas tube. We haven’t had any stuck chambers since I came up with the recent chamber, which is called the Noveske…the acronym, which we write on the barrel is "NMm0", and that stands for Noveske Match Mod 0. It’s a chamber that gives you 100% reliability with as much retained accuracy as possible. You can have a more accurate chamber design, but you sacrifice battle-grade reliability. You can get stuck cases and other things with different chambers.
So, from the chamber, our barrel is hardness-tested again, just to make sure we didn’t lose any hardness in the heat-treating process, and every barrel is serial-numbered at that point. So, now, all the information about the barrel, the heat-treat lot, the packing slip number, the bar number, all that information is now attached to the barrel with a 6-digit serial number, and it goes through the rest of the process with all the information attached to it by that number. And, we keep a log book with every end-user and every bit of information, just in case there was a problem with one customer’s barrel, we can track down all the related barrels and pull ‘em in in an efficient manner. And we’ve never had to do that, but I can if I need to.
Crane: And all the barrels are polygonal-rifled, right?
Noveske: All the stainless barrels have…that button that we designed, I call "Improved Polygonal". The polygonal that I used in the past and that some other people are using has one shortcoming, which is an unpredictable end-of-service life. It goes from shooting great to tumbling bullets. Our barrel now gives you a predictable end-of-service life. As it’s shooting out, it’s going to open up in group before the bullets tumble.
Crane: And how many rounds are you gonna’ get out of that?
Noveske: I don’t know. I know of barrels that are over 15,000 rounds still in service. So, I don’t know how long they’ll go, but I know that they’re going quite a ways.
Crane: What about the chrome-lined barrels? Are those polygonal, too?
Noveske: Those are strictly made to the TDP for the M249, so they’re a 6-land-and-groove MILSPEC conventional land-and-groove with a 5.56 NATO chamber.
Crane: If you’re settin’ up an AR carbine for somebody, most of the time, are you gonna’ recommend the stainless polygonal?
Noveske: Well, it depends. I ask them what they’re gonna’ do with it. The stainless-barreled uppers and rifles that we sell are a precision carbine. The chrome-lined light carbines are…for the guy that says he’s gonna’ beat it up, he’s gonna’ abuse it, he’s gonna’ train hard, he’s gonna’ do full-auto mag dumps, that’s the gun for that kind of treatment. The guy that’s gonna’ be sniper, counter-sniper, or anything precision…
Crane: What if you’re doin’ a lot of…let’s say you’re gonna’ compete in 3-gun with it on semi-auto, and you’re just gonna’ do a lot of rapid fire semi-auto shooting and stuff like that, then what?
Noveske: Either one’s fine. They’re both very accurate. I’ve got groups that people have sent me with both barrels under half an inch at 100 yards, so it’s kind of like I’m competing with myself.
Crane: If you’re looking at both the stainless barrel and the chrome-lined barrel, what’s standard MOA on these guns, on these barrels.
Noveske: Stainless barrels–and I’m not sayin’ this from what I’ve shot. This is reports from customers—The typical end-user report on my stainless barrels is about .6 MOA, and the Light Carbine barrels, most everything I hear is sub-MOA, and that means it can be three quarters of an inch [3/4" MOA] or half an inch [1/2" MOA].
Crane: So stainless is gonna’ be a little bit more accurate, but not much.
Noveske: Right, ’cause they’re both very accurate, already.
Crane: In terms of the rail systems that you’re usin’, you chose Superior Weapons Systems
, I guess, just because you liked the base rail that they were doin’, and you figured you could just…