Shilen is against fluting but Hart is not. Does fluting adversely affect accuracy? Anyone with experience in this matter?

Bobby B.

Any time you do machining or grinding on a barrel you can introduce unwanted stresses and harm accuracy ! Done carefully it's ok but for the trouble you don't really reduce the weight all that much.

Only if the flautist is playing some really funky, offbeat jazz tune...otherwise its a pretty soothing type of music.

I really don't know the absolute answer to that; I assume if you can machine a barrel to a certain contour properly and not effect accuracy then yes, you can do other things if they done right.

Shilen sells a ton of barrels to the benchrest crowd and philisophically they are against anything that induces stress; that's why their rifling is shallower than most. The button with shallow rifling induces less stress than deeply rifled buttons. That, and benchresters are trying to bump the absolute max weight in their class for stability so lightening a barrel is counter-intuitive for that purpose. And Shilen barrrels win a lot of matches.

On the other hand, once upon a time and maybe even now, 1000 yd rifles had extensive machining done to their long barrels, even rings cut circumferentially, not longitudinal flutes and those guns won matches too.

Some say (and I remember a pretty long thread but not the conclusion) that fluting acts like corregation and stiffens a barrel. Seems to me maybe a lighter barrel or when the bore is a significant percetage of the O.D. but how much can it help a tube already 1" in diameter with a .224 or .243 hole in it?

OK Here is what i recall on fluting. I was looking into having a barrel fluted. the fluting and contouring must be done prior to drilling the hole and remaining barrel making steps. Why do you do that way?? what was seen was when the flutes were opening up the bore diameter according to the air gauge. i don't recall the amount So the flutes relieve tension on the bore if they are cut after the hole is drilled, the bore expands and so the bullet goes through tight and loose sections of the barrel. as far as stiffness goes the barrels stiffness is the same but done with less weight. I do not recall how the stiffness can compared from a light barrel versus a heavy barrel that fluted. intuitively the more steel further from the bore center line the stiffer a barrel will be. I'd go look on lilja's website, rifle barrels.com i think, that fellow Jesus freak will have wise insight into this matter.

I was in Phoenix, Az a few years ago when Skip Otto shot a .099-5 shot group at 200 yds. Being that he fluted barrels for a living, he shot a Shilen fluted barrel.
Butch

From reading Hart's website, they flute the barrel prior to final lapping so as to maintain tolerances.

Bobby B.

I can offer this as proof of what is attempting to be accomplished by fluting . Rigidity !.

Anyone ever look at Drill Steel , I'm talking industrial Rock drilling machines . Stiffness is the primary aim also to a degree is to lesson the weight of the drill rod . All Drill steel is FLUTE CUT making if Hex or Octagonal when viewed from the end . Spiral fluting is more for decoration than stiffness IMO any way .

Shoot Straight Know Your Target . ...

Dr. K
Fluting does not do anything to increase stiffness or otherwise to steel.
Butch

Fluting a barrel-any barrel-REDUCES its stiffness. There is nothing grey about it, this is 100% fact for any cylindrical object in the universe.

The problem with this story getting all cocked up years ago is the herd of today's gunwriters. There are still a few who are good, but it is a small percentage. Gunwriters with no engineering degree read soemthing-usually advertising hype posed as information-and without understanding the subject or even its context, assume it applies to toally unrelated areas. If they were not so ignorant of facts and the laws that govern the goings on in the universe, they would be embarrassed by what they write. Again, there are a few good ones, but they are in the minority.

For two equal length cylindrical objects OF THE SAME WEIGHT, if one started out as a larger diameter and was fluted until it weighed the same as the smaller cylinder, then the larger one would be stiffer. BUT IT IS LESS STIFF THAN THAT IT WAS BEFORE THE FLUTING! THE FLUTING MADE IT MORE LIMBER AND WHIPPY, WHEN COMPARED TO ITS ORIGINAL FORM!!!

THis has only been discussed on this very forum a minimum of 25 times. That is a very, very, very conservative estimate.

BTW-no, THE BARREL FLUTING DOES NOT INCREASE THE COOLING RATE OF THE BARREL!!! If you don't believe it, then go to engineering school and when you get out in 5-6 years, run the calculations yourself. The barrel would have to be above its critical temperature with a heavy crosswind to get enought convection and forced convection to be measurable and be statistically above the sampling noise.

This has been brought up a minimum of 25 times as well.

Hell, the original question posed on this thread has been approximately 1.33 oodels of times.

Any time I am new to a forum and have a question, I use the search function before asking questions. 99 times out of 100, my questions are common and I cna find some really good info in old forum pages. I feel it is the only polite way to intorduce myself to a new group of folks who I hope can help me learn things in the future. I guess I am just funny that way.

quote:

Fluting does not do anything to increase stiffness or otherwise to steel.

A fluted barrel is stiffer per unit weight than a round barrel.

Lilja's site has a good discussion of this.

http://www.riflebarrels.com/products/barrel_length_fluting.htm

In the "if it is done right" category i would leave it to the barrel makers to do...

Cheers,

Dan

FWIW, I've got a fluted Shilen barreled .300 WM with a muzzle brake on a pre-64, as far as I know all the work was done by Shilen, I bought the gun very slightly used. The barrel is 26 inches long and not overly large in diameter. If fluting hurts the accuracy, I'd hate to see what it would have been capable of if left alone. It will group any decent load into 1/2 inch or less at 100 yards, I have shot several in the .2s but I don't shoot it at paper much ( I don't know how much barrel life there is, but I plan on using most of it on critters), and this is without working up specific loads for the rifle. I've killed quite a few deer, hogs, and coyotes with this rifle, plus assorted other pests......luckily they don't require the level of accuracy a non-fluted barrel would provide.

I think fluting looks neat, just like I think octagonal or round to octagonal barrels look neat. Would I pay the extra for the "look"? No, but I'll take it when it comes with the rifle and not worry about it.

quote:

Any time I am new to a forum and have a question, I use the search function before asking questions. 99 times out of 100, my questions are common and I cna find some really good info in old forum pages. I feel it is the only polite way to intorduce myself to a new group of folks who I hope can help me learn things in the future. I guess I am just funny that way.

take two midol and a snickers and call your mother.

just kidding, but...

the guy simply asked a question. poking around in old archives is pretty dry compared to seeing answers to a question that you yourself wrote. some folks like the interaction.

quote:

Originally posted by Marc_Stokeld:
Fluting a barrel-any barrel-REDUCES its stiffness. There is nothing grey about it, this is 100% fact for any cylindrical object in the universe.

'Splain something to me Marc, why is it easier to push a cylindrical barrel straight than one of the same diameter that is fluted? What is it that the flutes do that make it not want to behave?

If shapes don't matter to a structures Rigidity , why bother to have anything other than flat ?.
Having a degree Ms.D in structural engineering in addition to also having a Ph.D in Organic Chemistry .

Let me assure EACH and everyone of you SHAPE MAKES A HUGE DIFFERENCE in a structures RIGIDITY as well as strength . Corrugated tin ,copper ,steel, of the same gauge will support far more load than a flat piece . There for by altering shape it's now stronger !.
How much is another discussion . In addition it also increases surface area for better cooling .

I for one believe this is why octagon barrels were used in older rifles , they were harder to bend than round stock . That's just IMO on that I have nothing to base that on .

Shoot Straight Know Your Target . ...

quote:

Originally posted by Dr.K:

I for one believe this is why octagon barrels were used in older rifles , they were harder to bend than round stock .

I have 30 years experience bending barrels so I can attest to that!

I'm not an engineer but...

I think the problem with this type of discussion tends to revolve around comparing apples to oranges.

If you take a barrel of say 1" diameter and compare it to a fluted one also of 1" diameter I suspect you would find that the fluted one weighs less but is not stiffer. For barrels of the same weight but one being fluted I'd suspect the fluted one is stiffer BUT it also has a larger diameter. Although everyone has their pet theory.

I wonder what diameter (max or min) those octagonal barrels were compared to the round ones.

Just my 2c

Copidosoma is correct. If both barrels are the same length and diameter, the unfluted barrel is stiffer. Dr.K, you are not talking apples to apples.
Butch