Noveske Barrel Break-In (Stainless Steel)

[Cameron]

It is interesting to note that FNH uses chrome lining on the bores of their precision bolt actions and they have shown themselves to be some extremely accurate rifles.

Cameron

[Robb Jensen]

It is interesting to note that FNH uses chrome lining on the bores of their precision bolt actions and they have shown themselves to be some extremely accurate rifles.

Cameron

Their barrels are hammer forged and they do their chroming totally different than anyone else in the industry. They won't say how they do it but it's basically match grade barrels which are chrome lined. Their bolt guns use M240 barrel blanks.

[Cesiumsponge]

I'm late chiming in here, but I feel the photos on the first page are incomplete and photos are nice to look at, but give no quantifiable data. Why do we have a "before and after" of one barrel but not the other? What did the Afghan barrel look like before 150 rounds of "break in"? The "after" photos show tooling marks on the Afghan that appear to the eye as deeper than the Kreiger barrel even when it was new so it would require a great deal more material removal (500, 2000 rounds?) to wear the barrel to the point where it disappears. The Noveske barrel simply isn't as refined as the Kreiger (nor would we expect a hand-lapped finish on a non-hand-lapped barrel)

I'm not for or against the breaking-in procedure because I don't have empirical data, only anecdotal accounts. There are plenty of discussions of this procedure on benchrest forums and those folks win or lose by accuracy so I tend to believe them since their entire sport is based on minimizing or removing factors stacking against accuracy. It's plausible that removing perpendicular tooling marks to the direction of bullet travel results in more consistency in groupings and there seems to be a loose general consensus, but certainly not on "how to do it" because every barrel maker seems to have their own black magic recipe for break-in.

Most of us shooting black rifles don't hand-load for small groups and meticulously record every round and the environmental conditions. I think most shooter and environmental factors will affect accuracy long before fine tuning the finish of the barrel so break-in might simply be irrelevant to many of us. I've heard claims that breaking in with a hundred rounds is a scam by manufacturers to wear barrels out faster and this might be a plausible paranoid argument for barrels that wear out in 1500-2000 rounds but doesn't really seem like a useful scam in barrels that can exceed 20,000 rounds of useful service life. Selling company T-shirts and patches will turn a better profit than shortening the life of barrels by less than half a percent. Many of us don't ever hit that type of round count, but we're happy to rock a new branded hat.

Anyhow, a bore scope image doesn't give you an empirical measurement. If gives you an uncalibrated photo where you can come to any number of conclusions based on lighting and angle. If someone says "obviously photo one is rougher than photo two", I can ask "by how much?" and the answer will be "???".

Did anyone actually take a profilometer to measure the surface roughness in a quantifiable manner, then compare the figure on both barrels before-and-after? These are two barrels from two makers with what I assume are two very different levels of refinement, made on different equipment, made in a different manner, and made of different materials, and of different hardnesses and treatments. One is a hand-lapped match barrel and the other is a barrel made for heavy duty use. Comparing two unrelated barrels establishes nothing.

I use contact profilometers in my line of work. The eyeball or fingernail, or microscopic picture does not give you a quantifiable unit of measure for surface roughness. A profilometer gives you a quantifiable arithmetic mean value (Ra) in microinches, which is an average deviation between the microscopic valleys and peaks of a surface. That is the only way to give an actual useful, measurable figure to properly make comparisons. If you're measuring one barrel with with a reading of 10 microinches and another that scratches at 15 microinches, the later barrel will look rougher still if both undergo the same number of round counts. If I say "picture one is rougher than picture two by 3 microinches", that is a quantifiable unit of roughness. Until we put everything under a scientific test and standardize the means in making comparisons with scrutiny of methodology, and repeatable results from multiple parties, they're just interesting intellectual arguments (enjoyable though!)