Fluted Barrels: Good or Bad?

Clevinger

New member
What are your thoughts on the pros and cons of fluted barrels?

It seems like some reputable companies like Winchester and Sako use fluted barrels, supposedly for heat dissipation and reduced weight. If they can put their name behind them I tend to trust them.

However, some sources I've found allege they lead to barrel warping and reduced accuracy. Presumably shortened barrel life as well.

Is there a consensus FiringLine opinion on this matter?
 
Good luck on getting a consensus on anything at all out of this bunch, though everyone might agree that reloading is good and Kate Upton looks good in a small bathing suit.

As for barrel fluting, I've just heard the same stuff you have, and would also like to hear the truth. Unfortunately, I just might not recognize the truth if I heard it. I'd be more inclined to buy a rifle with a fluted barrel from some maker like Sako than I would to have a bull barrel fluted.
 
I have both bull and fluted barrels on some of my AR platform guns and all I can say is fluted is lighter.
As for does it run cooler - your guess is as good as mine.;)
 
I've always kind of thought of it as a weight saving/cosmetic thing. I wouldn't mind a fluted bolt, because all the functional parts are totally unaffected, recoil lugs, etc. I would never have it done to any barrel though(I want all that metal!). However, I am a little envious when I see someone at the range take out there prettied up bolt gun with a spiral fluted, stainless barrel.:cool:

Like so many things with firearms, it's just personal preference. If you like the look (or really despise heavy rifles) then do it!
 
Neither good nor bad. Mostly just different. In theory they probably cool a bit faster, but I doubt if it is enough to matter. Probably their only real asset is that they allow you most of the benefits of a heavier barrel, but a few ounces lighter.

Based on what I've read an unfluted barrel of the same diameter is still stiffer, and in theory more accurate. But a fluted barrel can be larger in diameter and will tend to be more accurate than a thinner barrel of the same weight.

So they tend to be a compromise for the guy wanting a little stiffer barrel for accuracy, and something a bit lighter. I have one of the Winchester EW's with a fluted barrel. If nothing else I like the look. It is quite accurate, and a bit lighter than a standard barreled gun.

The fluted Winchester Extreme Weather and Featherweight are good examples. The EW uses a standard diameter barrel with flutes, while the FWT uses a thinner unfluted barrel. Both weigh exactly the same. Both the FWT and EW are 4 oz lighter than the standard weight barrels in the same calibers and barrel lengths. Two approaches to the same problem and in my experience the fluted EW barrels are going to be a touch more accurate.
 
Ive read that while a fluted barrel will cool quicker, it it also heats up quicker than a solid barrel of the same profile due to the decreased thermal mass but increased surface area. So a heavy barrel will get you more quick shots before overheating, but a fluted barrel will cool down faster for repeated intermittant shooting. Thats why you see more varmint a benchrest rifles with bull barrels and hunting rifles with flutes. Personally, I prefer a bull barrel, but I dont carry my guns on my back all day... I can see the attraction for hunters.
 
How about "indifferent!" I have a few fluted barrels, they aren't any more accurate, they don't reduce the weight that much, and they don't cool down noticeably faster. They do look nice in certain applications so they are a "I'm okay with or without them" option. It isn't going to be a deal breaker on if I'll purchase a rifle or not.
 
This very same subject came up at my place between my sons and I, and from what we read were still undecided on even the looks of a fluted barrel...
I think its a machinest trick to get more of my hard earned dough.


Who the hell is Kate Upton?:rolleyes:
 
I like the way they look and it doesn't hurt anything if it's done right.

A fluted barrel is stiffer than an unfluted barrel of equal weight and lighter than an unfluted barrel of equal stiffness.
 
From a heat generation perspective, a fired rifle will not generate more heat with a fluted or with a non-fluted barrel. The cartridge being fired generates the same amount of heat regardless of barrel thickness or fluting. A fluted barrel or a very thin barrel might feel hotter (and actually be hotter faster), but that's just the heat reaching the surface of the metal faster than it would have in a bull barrel. One thing that a fluted barrel should do better is to transfer the heat to the surrounding air. It has more square inches of surface area than a round barrel has and that will allow the faster heat transfer and faster cooling. I wouldn't imagine that fluted or non-fluted will automatically and always be more or less accurate unless the fluting of the barrel creates uneven stresses in the barrel that were not there before the fluting.
 
Who the hell is Kate Upton?

Google it. You'll be glad you did.

Back to the subject, fluting reduces weight, it's stiffer than a non-fluted barrel of the same weight because it can be larger diameter for the same weight. Fluting an existing barrel will make it lighter, but not stiffer.

Heat dissipation advantages would be small enough to be more theoretical than practical.
 
So in theory then. The fluted part of the barrel will heat up faster and uneven compared to the rest of the barrel beinging it is thinner?.
 
Well, if a fellow wants to get real picky about the heat transfer, the bottoms of the flutes will get hot faster and then the sides of the flutes and then the outer surfaces. Just a wild guess, with no mathematical backup data, and I'm thinking that the surface area of a deeply fluted barrel might actually have as much as 2/3 more surface area than a non fluted barrel. But on the other hand, a very thin barrel gets real hot real fast, which may promote fast heat transfer. And a heavy bull barrel is quite a heat sink, so maybe the heat moves away from the bore faster, but leaves the metal slower.

So Ok...let me retreat to something that I do know about, and that is oil refinery heat transfer. That was part of my field of expertise a very long time ago. We used finned tubes in heat transfer equipment that relied on removing heat from processes by using air blown across the fins on the tubes that were filled with hot flowing oils. Those fins are vaguely kinda sorta similar to the logic of using a fluted gun barrel to remove heat though the fins added a huge amount of metal surface area, whereas a fluted gun barrel doesn't add so very much surface area.

And all the above and a buck will buy you a cup of coffee, unless you are at Starbucks. And the true value of flutes is probably simply a way to maintain barrel stiffness with less barrel weight. And maybe it cools a little bit faster.

What I still don't know, and have always wondered, is whether or not a fluted barrel is as accurate as a non fluted barrel of the same outer diameter. I can't imagine that it would necessarily be MORE accurate. Does fluting introduce any potential that accuracy will be reduced.
 
Fluting your barrel works a bit like the heat sync on your computer's processor. It gives more surface area for the cooler air to touch and start to dissipate the heat generated by the bullets being fired.

As far as stiffness, as far as I know and have been taught, the barrel is as stiff as a barrel that is as thick as the overall barrel diameter from the bottom of one flute to the bottom of the flute on the opposing side. I would not say they have a problem or tendency to cause barrel warping.

I've never shot one, but tend to believe the benefit is that of the machinist making a extra few bucks.
 
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Fluting will increase barrel stiffness. A crude example would be I-beams in large buildings. If you took the same material and made a solid bar it will not be as stiff as the I-beam. Theoretically it should also cool faster because it gas more surface area. As far as heating up faster...the initial temperature is the same and the bore surface area is the same. The outer temperature is dependent on the distance to the outer surface.
 
a fluted barrel will be less stiff than a non-fluted barrel of the same outside diameter, simply because it lacks the same amount of structural material. If you'd like to demonstrate this, take a wooden pencil and flute it, then compare it's rigidity against a non-fluted wooden pencil.

It will however be stiffer than a barrel of the same interior diameter as it has more structural mass (as measured at the bottom of the flute).

As others in the thread pointed out, a fluted barrel has less thermal mass, therefore heats up more rapidly, yet cools more rapidly than a non-fluted barrel of the same exterior diameter.

I find myself looking at what the pros use. When you look at the folks going after ultimate accuracy, the extreme distance and bench rest shooters, a fluted barrel is extremely rare in this arena. Since these guys are constantly experimenting to ring out the last micron of accuracy from their rifles, one must infer that fluting is of no benefit to their sport.

On the other hand, look at the professionals that lug their weapons over miles of rough terrain. Fluting is fairly common and there lies the only benefit - weight reduction.

I have three rifles with fluting. This was strictly a cosmetic preference and not a performance based decision.
 
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