rifle barrel fluting

[kuca_2004]

I am looking for someone who does barrel fluting. I have 2 barrels I would like done. let me know who does it.

[Bart B.]

Here's a 'smith who flutes barrels:

http://www.hbrifles.com/gunsmithing-services

Two cautions are in order.......

Note your barrels may well not be as accurate after their fluted, especially if they're button rifled or hammer forged. The bore and groove diameters change a little bit under the flutes. Broach or single point cut rifled barrels' accuracy usually doesn't change much at all after fluting, but it depends on how it's done.

They'll also be less stiff. Metal's removed that originally resisted bending.

[kuca_2004]

Ok thanks for the tip. I was kind of wondering if it would weaken the barrels any. Both my rifles have the bull barrel. One is stainless steel and the other one is not. I have a DPMS LR-6.5 with the stainless steel barrel and a Weatherby Vanguard 22-250 bull barrel.

[Dixie Gunsmithing]

The Weatherby has a hammer forged barrel, although I don't know how much, if any, fluting might cause the bore to open, since the ribs of the flutes act as stiffeners. Also, it is according to how deep the flutes are, and how many. If it does not cause it to open, it can still affect the accuracy over barrel whip and resonance. You take that chance any time you do major machining on a barrel.

The other, I am not sure, as I don't know who's barrels they use. Since Panther is a gun builder, they buy barrels, or that is what I've been told. I doubt the barrel is hammer forged if it is stainless, and may not be button rifled either. Most stainless is very hard to rifle these ways, if not impossible, over work hardening.

[fineredmist]

Removing metal from a barrel will reduce the stiffness of the barrel and any increase in the amount of radiating surface to improve cooling is not worth talking about. The reduction in weight is also not worth talking about. Cutting flutes is an advertising gimmick and sometimes looks "cool" but does nothing constructive.

[old roper]

Here another gunsmith that does after market fluting.

http://kampfeldcustom.com/boltfluting0914_003.htm

[tobnpr]

Not an engineer, but the evidence/explanations presented here make sense to me.

http://www.snipercountry.com/article...relfluting.asp

A fluted barrel of the same weight is stiffer than non-fluted. Fluting will reduce weight. It seems clear that the rate of cooling will be greater due to the lesser average distance to the surface of the barrel (not as much greater surface area), but I wouldn't see that as a consideration where a lightweight barrel would be needed.

I suspect, if there were a real and quantifiable advantage to this, the military would have adopted it in platforms like the M40.

[Bart B.]

Winchester's web site claims there M70 Extreme Weather fluted barrels are stiffer and lighter than the standard barrels. They're both the same outside profile. I've been on their case for years to correct the false info on them being stiffer. Some of their tech reps I've talked with agree with me. I've thought about betting a free rifle from them if I prove them wrong. It's easy to do.

[Dixie Gunsmithing]

Bart, they're not as stiff as a solid bull barrel, but are stiffer than a tapered barrel, with smaller diameters. They can not be stiffer than a stock plain tapered barrel. They ought to watch their advertising, as they can get in a bit of trouble if something happens, and they are proven wrong.

[jmr40]

My Winchester EW with fluted barrels and the Sporter measures .625" at the muzzle. The Featherweight .560". It is hard to get an accurate weight comparison because of differences in stocks, scopes and mounts etc. But I can say that all things being as close as possible the FWT and EW are pretty darn close in weight. As near as I can determine the barreled action of the FWT should be the lightest, about 1-2 oz lighter than the EW, The Sporter is 6-8 oz heavier.

In all honesty for 2 shots there isn't a bit of difference, but for strings of 3 or more the thicker barrels, fluted or unfluted are much more accurate. Not sure if it is relevant or not, but the FWT is more picky about which loads it shoots well. The 2 guns with thicker barrels are generally accurate with most any load I put in them.

In my experience the flutes do reduce weight comparable to a much thinner barrel, without giving up much, if any accuracy. I don't see how they could be stiffer and stronger than an unfluted barrel of the same thickness. But if done right they don't seem to give up much. If they do I'm not good enough to notice it.

Winchesters website may have made some claims in the past about stiffer fluted barrels, but as of tonight they only say.

SPORTER WEIGHT STAINLESS STEEL, FREE-FLOATING FLUTED BARREL reduces weight and improves cooling

Seems like an accurate description.

[Bart B.]

In all honesty for 2 shots there isn't a bit of difference, but for strings of 3 or more the thicker barrels, fluted or unfluted are much more accurate.

I've never seen any proof of that in properly fitted skinny match grade barrels to receivers whose face is trued up. Those skinny barrels shoot just as accurate as thick ones of the same length. For example, that 30" long skinny, whippy Palma barrel this gal had at a match that tested just as accurate as much thicker ones of the same length; both shooting the same ammo into 1/2 MOA at 600 yards with 17+ shot strings. Her coach told me she may have had the most accurate rifle on the team in spite of all the other barrels of the same length were thicker.

My skinny ones shot the same accuracy level as my thick ones with 20-shot test strings.

There's no secret at all. Just remember that all barrels whip at their own unique resonant frequency and harmonics thereof for every shot fired. They're the most repeatable thing in the entire shooting system comprising rifle and its parts, ammo and its components and that human holding it.

Any barrel that's not fit squarely to the receiver will walk shots as it heats up. Those properly fit will shoot dozens of shots to the same point of impact at long range; short range, too, all fired once every 20 seconds.

[T. O'Heir]

Fluting is purely decorative and doesn't do much of anything. Certainly does not reduce the weight significantly, if that's the plan. Doesn't add to cooling either. There's was a serious study about it some place on line. Was not recently that I read the thing, so I've forgotten where.
Winchesters website is a marketing tool and nothing else.

[Bart B.]

Winchester's web site; two minutes ago:

http://www.winchesterguns.com/produc...01c&mid=535206

states:

The fluted barrel allows us to give you a stiffer barrel profile that does not carry excessive weight. So the Extreme Weather SS feels very light but offers accuracy of a heavier rifle.

Same words in different ways have said that on their site for decades.

[std7mag]

Here we go again!!!

Alas, it is not just the mass of a metal object that determines it's "stiffness".

With metal, form is part of function. You can remove metal, and make it weaker, but also you can remove metal and make it stiffer. It depends upon how it is done. Or rather, the form of which you do it.

Example:

Take a piece of sheet metal, like you would fashion ductwork from. Lift it up from one end, it's flimsy, easy to bend.
You can take it, and put it in a break, and bend it just enough to make a raised "X" across it. It is much more stiff now.
Now take same kind of sheeting, and drill holes in it. Along the holes you raise the bend the lips up. It is much lighter, and much stiffer now.

It is not just a form of mass. what kind of metal, the heat treating, and the form all have effects on metal.

As for the OP's original question, you may want to contact Douglas, or Hart, They make barrels, along with fluting, so may for a price be able to do yours.

[phudd]

The advertising is deceptive. A fluted barrel is stiffer than a non fluted one of the same weight. Fluting a barrel only makes it lighter, not stiffer or more accurate. It is a better method of lightening than reducing the diameter.

[Dixie Gunsmithing]

std7mag

In mechanical engineering, this is calculated around several things, but the most important is the section modulus. Thus, if a piece of steel is thicker than another, the thicker piece is stiffer and stronger, and it's modulus is higher. It is according to the profile of the section, and what it's section modulus is. Thus, a bull barrel, will be stiffer than a fluted barrel that was made from a bull barrel that size, but the fluted barrel would be stiffer than a smaller diameter and tapered barrel, where the flutes would have been added to it's section. In other words, while fluting the bull barrel, the minimum diameter, at the bottom of the flutes, would have been equal to the diameter of a standard tapered barrel. All three would have a different section modulus, with the standard tapered barrel being the lowest, and the bull barrel the highest.

A simple test would be to take a 2 X 2 angle, that is 1/4" thick, and a 2" square solid bar, and apply a weight to both. The angle would give before the bar, thus the angle would have a lower section modulus than the bar did. However, the angle would have a higher modulus than a 1/4" thick by 4" wide flat would have.

The only problem is, when you do any major machining on one, barrel whip and resonance can change, and you may end up with a barrel that won't be accurate. I saw this on a .22-250 once, and the thing would ring like a tuning fork for 2-3 seconds after you fired it. I installed a dampener on the end to tune it out. Factory fluted barrels would compensate for this in their design.

[Bart B.]

Std7mag, folding metal adds weight at right angles to its dimension across the folds. That's the compromise. A 1" tube with 1/10" thick wall has a circumference of about 3 inches in the center of its wall. If you sliced it then folded that 3" wide strip into 3/10" V's, how do you make a 1" diameter tube with that folded metal? Could you do it if the tube wall was only 1/100" thick? For every fold, the width of that strip gets less. Watch the ends of an accordion get closer together as its bellows' fold; the more they fold the closer ends get.

Bending that sheet metal middle into an "X" shrinks its outside dimensions. It's a variant of the above. If it's outside dimensions stay the same, then some of it is thinner than before.

When you flute a barrel, you've removed metal that made it stiff. There's less metal to resist bending.

Same thing with a deck built with vertical 2x6's against each other. If you replace every other one with a 2x4, is that deck stiffer or stronger?

[Ritz]

That's an interesting argument for an "oblong" barrel.