It's never pleasant to be wrong in print, and I appreciate it when a reader sets me straight.
In this case, a reader challenged a statement I made about fluting increasing the rigidity of rifle barrels in a review eight months ago about Remington's new rifles. I also wrote that fluting actually increases the surface area of a rifle barrel, improving its ability to shed heat while also increasing strength.
None of that is true, my reader insisted. Removing material cannot increase the strength of a metal structure. It can only weaken it. Fluting is merely a cosmetic effect that has no positive effect whatsoever on performance. If it did positively effect performance, he added, benchrest shooters would use fluted barrels.
My reader said I repeated manufacturer's marketing hype, and that's how marketing hype becomes accepted as fact.
That stung. I have written those statements frequently. I did not like the idea of having reinforced falsehood. He compelled me to do what I should have done a long time ago. I measured the surface area of my Remington 5R's barrel. It has three narrow flutes cut into the barrel. At least half of the metal is intact, forming a triangle. This is important for later.
First, I measured what would have been the barrel's uncut circumference from the top of the tops of the uncut surfaces. Then, I measured the actual metal surface of the uncut tops and the flutes. The measurements were exactly the same. Fluting does not increase surface area.
On the matter of fluting affecting barrel strength, we are both right.
Fluting certainly will weaken a thin style barrel because there is already so little metal between the bore and barrel's outer surface. However, barrels like those used on my Remington 5R (6.5 Creedmoor), Remington VSSF (220 Swift), and Savage Model 110 Predator Hunter (22-250), have wide-countour, bull type barrels. Their flutes are fairly shallow. A 22-caliber bore makes a very small hole in the center of the thick blank, so there is a lot of metal between the troughs of the flutes and the bore wall.
A .264-inch diameter hole is a bit wider than a .223-inch diameter hole, but the wider diameter of the Creedmoor's barrel offsets the difference. The Swift's barrel has an outside diameter of 2 3/4 inches. The Creedmoor's barrel's outside diameter is 2 7/8 inches.
Also, the width of the Creedmoor's three uncut surfaces is 1/2 inch. That means 11/2 inches of the original circumference is intact. The Swift's barrel has 6 raised, or original, surfaces and six flutes. The original surfaces are 1/4 inch, which means, again, that 11/2 inches of the original circumference is intact.
Because a triangle is a stable structure, and because the Swift's barrel is essentially two interlocking triangles, fluting does not affect the structural integrity of either barrel.
The function of fluting on these barrels is to reduce weight, which theoretically makes a hunting rifle more portable. Fluting does not increase portability for either of these rifles. Even with a fluted barrel, the Remington 5R is heavy. Three days carrying that rifle across the prairies of Cimarron County, Okla., last fall while hunting pronghorn antelope convinced me to never do it again.
A dedicated varmint rifle like the Remington VSSF is meant to be used on a rest to shoot at prairie dogs from long distances. Weight is not a consideration for that application, so decreasing some weight by fluting the barrel does not improve that rifle's functionality in any sense.
In the Creedmoor's case, fluting didn't hurt or help. Both rifles are simply too heavy to carry. They must be used from a rest, from a stand, or with a bipod. I mounted a bidpod to the 5R expecting that I would have to shoot at an antelope at long range from a prone position. The bipod added a lot of weight, which further undermined its adequacy for the task I assigned it.
A lot of things affect a rifle's accuracy and utility. Much as I hate it, I have to agree with my reader. Fluting is not one of them, and if applied to the wrong kind of barrel or applied ineptly, it can actually affect it badly.
A fluted barrel looks cool, so there is that.