Does anyone know a reputable, dependable shop/person to helicaly flute a barrel? E.R Shaw can do it, but only to their own barrels. My customer is not interested in using one of their barrels at this time.
Thanks

Some members of Snipers Hide recommends ; http://www.kampfeldcustom.com/index_022.htm

http://www.kampfeldcustom.com/index_035.htm

I recently saw a fine looking .338 Lapua Mag with a staggered stop fluted barrel at a shoot , I was impressed not only with the looks but it's performance as well . I'm seldom jealous of others possessions but man that was a nifty shooting head turning set up .

I'm considering offing a few of my things so as to purchase a similar setup on either a Barrett or Savage setup .

Doc,
I agree, Karl Feldkamp is very good and also a good guy.
Butch

Shaw has a patent on it. If anyone else is doing it they are going to get a letter from Shaw's attorney as soon as Shaw finds out about it.

John

That was quick, the Kampfield site now says that spiral barrel fluting is temporarily unavailable.

Didn't think you could patent something like that, but have been known to be wrong before just ask my wife.

Give Bobby Hart a call--570-752-3655 Eastern Standard Time, RW Hart & Sons, Nescopeck, PA.

He does inturrupted, spiral and diamond flutes on CNC machine.

quote:

Shaw has a patent on it. If anyone else is doing it they are going to get a letter from Shaw's attorney as soon as Shaw finds out about it.

He has a patent on cutting a helical grove on a cylinder? Methinks his tooling might have a patent, but if there is another way so skin that cat i can;t imagine how the design is enforced. Does this mean he has a patent on rifling then? If not, then i;m going to apply for one...

quote:

Originally posted by BaxterB:

quote:

Shaw has a patent on it. If anyone else is doing it they are going to get a letter from Shaw's attorney as soon as Shaw finds out about it.

He has a patent on cutting a helical grove on a cylinder? Methinks his tooling might have a patent, but if there is another way so skin that cat i can;t imagine how the design is enforced. Does this mean he has a patent on rifling then? If not, then i;m going to apply for one...

Exactly ...

Er Shaw's web site states that the Helical fluted barrel is up to 30 percent stiffer than a straight fluted barrel.

Does this sound right?

Hal

quote:

Originally posted by Hal H:
Er Shaw's web site states that the Helical fluted barrel is up to 30 percent stiffer than a straight fluted barrel.

Does this sound right?

Hal

Stiffer how? What's the methodology? "...up to" means what?

email sent to Shaw:

"" As both a mechanical engineer and a custom gunmaker, I am very interested in your claims that the spiral fluted barrel "is up to thirty percent more rigid than a similar barrel with Straight Fluting," and am equally interested in your claim that "Helical fluting provides additional surface area for improved cooling, improved barrel harmonics, and helps to counter act rotational torque, giving the shooter greater shot consistency."

I would like to see your calculations used to make these claims. I would also like to see any FEA models or similar tools used to give you the conviction to tell clients, potential clients, and interested readers of your web site that these claims are indeed true facts. I have significant experience dealing with sensitive intellectual property and respect your right to not “lay all of your cards out on the table” and other desires to give away too many secrets, so to speak. However the basic calculations and data used to make these claims should be something that can be shared with interested shooters and gunmakers.

Thank you very much for your help.

Marc Stokeld "


I am awaiting their reply with bated breath.

I agree, total BS, but I don't have the $ or time to fight them. Why do you think everyone and there brother spiral flutes bolts, or diamond flutes barrels, but not spiral flute barrels.

John

www.twistedbarrel.com

I have used this guy for bolts. He done a good job.

James

Er Shaw holds a design patent on the helical fluting of rifle barrels. All it amounts to is a ornamental design. But it does allow the company to prevent others from reproducing the design until the patent expires. It's not a utility patent which would regulate a process. A design patent is image or shape. Similar to a Coke bottle But that also has a Trade mark which just about never expires so long as the renew it.

And the 30% stiffer depends on if the flutes are cut the same direction as the rifling or opposite. if the flutes are right hand and the riffling is right hand then the barrel is going to be less rigid

In all seriousness shaw is comparing straight fluting to helical. There are some questions you need to ask before you believe this kind of BS. One what is the base line?? How stiff is a plane barrel and of what caliber and twist rate of riffling?? Then how stiff is a straight fluted barrel and how many flutes and how deep are they cut?

The facts are fluting does two things mechanically to a barrel 1. It makes it lighter. 2. It creates more surface area to cool faster.

Fluting does not make a barrel more rigid or stronger based on the same barrel blank.

A few facts about fluting:
Fluting reduces wheight
a fluted barrel retains more stiffnes compared to reducing the wheight by turning down the barrel to the same wheight levell.
A fluted barrel (same O D) heats up faster due to less mass
Theoretically a fluted barrel cools down faster because of larger surfacearea
In practic this does not work as intended, as the top and buttom flute is not cooled, because the convection is thrapped
Theoretically this convection trapp, is eliminated by spiraling.
Fluting in some peoples oppinion looks better
Fluting gives the mfg a chance to earn easy monney

quote:

Originally posted by kcstott:
The facts are fluting does two things mechanically to a barrel 1. It makes it lighter. 2. It creates more surface area to cool faster.

Fluting does not make a barrel more rigid or stronger based on the same barrel blank.

A fluted bbl of a given length/weight will be stiffer than a non-fluted bbl of a similar length/weight.

The same MIGHT hold true for a spiral fluted bbl of a given length/weight compared to a straight fluted bbl of similar length/weight.

Not saying that it is in the 2nd instance, but iot might be.

KC is right.
Butch

You guy are miss understanding me.

What I'm getting at is if you take two barrels of the same length, caliber, and profile. And flute one of them it will not be stiffer then the other one. It will only weigh less.

A fluted barrel and non fluted barrel same length, weight and caliber. then yes the fluted one will be stiffer as it started out as a heavier contour

quote:

Originally posted by kcstott:
You guy are miss understanding me.

What I'm getting at is if you take two barrels of the same length, caliber, and profile. And flute one of them it will not be stiffer then the other one. It will only weigh less.

A fluted barrel and non fluted barrel same length, weight and caliber. then yes the fluted one will be stiffer as it started out as a heavier contour

I didn't mis-understand you a bit. As a matter of fact, that un-fluted barrel profile, once fluted will not only be lighter, I think it would be slightly LESS stiff than before it was fluted.

As you concured the same weight fluted barrel will be stiffer than a similarly weighted un-fluted barrel.(length & caliber being equal)

Using a fluted barrel will allow a stiffer barrel in a given weight rifle W/a given barrel length/caliber.

Not having an enginering degree I have no idea if a similar scenerio, weight/length/caliber, might be true when a helical flute barrel was compared to a straight flute barrel.

It just might be the case.

Well there is a difference in the rigidity of the barrel when it come to helical flute and straight flute But the difference is so slight as it would not be noticed by anyone other then a metallurgical lab

I'll be dipped in shit, there is a patent on this. Shaw is the assignee though, not the inventor. Carl Behling is the inventor.

I would be a little chagrined as a builder to receive a letter from a lawyer about this. I would prefer to follow Fred BEars example in patenting but never enforcing ideas to spread the use of such info and furthering the sport.

Still, there is a patent. I think i;ll go patent free-thinking now, seems just about anything is up for grabs.

The thing is you can slap a design patent on just about anything.

A design consists of the visual ornamental characteristics embodied in, or applied to, an article of manufacture. Since a design is manifested in appearance, the subject matter of a design patent application may relate to the configuration or shape of an article, to the surface ornamentation applied to an article, or to the combination of configuration and surface ornamentation. A design for surface ornamentation is inseparable from the article to which it is applied and cannot exist alone. It must be a definite pattern of surface ornamentation, applied to an article of manufacture.

In discharging its patent-related duties, the United States Patent and Trademark Office (USPTO or Office) examines applications and grants patents on inventions when applicants are entitled to them. The patent law provides for the granting of design patents to any person who has invented any new, original and ornamental design for an article of manufacture. A design patent protects only the appearance of the article and not structural or utilitarian features.

quote:

Originally posted by kcstott:
Well there is a difference in the rigidity of the barrel when it come to helical flute and straight flute But the difference is so slight as it would not be noticed by anyone other then a metallurgical lab

I'll buy that. As far as it applies to a given starting (pre fluting) profile.

What about the fact that since the helical fluting would remove more material in a given barrel length? More material removed = more weight removed. Therefore, a larger diameter profile could be used to achieve a given barrel weight. (length & caliber remaining constant)

Would that add to the stiffness in a more significant way?

There would also be a significant increase in surface area though so I would suspect that there would be a proportionate increase in cooling.

Don't get me wrong. I'm not going to run out & get a helical fluted barrel. (even if I could afford such superfluos luxuries)

After all, I'm the guy that uses milsurp & discontinued ER Shaw barrels to keep initial cost down.

Now we're getting into the design aspects of the fluting. Now without plugging all this in to a model there is going to be a point at which you can only remove so much material before you start to defeat the fluting process and make the barrel less stiff then it was to begin with. but in general terms you are correct.

Even an I beam is flimsy if you roll it over 90*
But it started out as a very rigid a light profile

Thanks for all the responses. I have sent an e mail to Karl Feldkamp asking if the spiral fluting would be available again in the near future. As of yet I have not heard back from him.

Dave, thanks for the reminder about Harts interrupted fluting. I have seen a rifle with this and loved the look. I am going to run this by my customer and see if he has any interest. He simply wants the bolt and barrel fluting to match. Lets see what happens.

quote:

Originally posted by BaxterB:
I'll be dipped in shit, there is a patent on this. Shaw is the assignee though, not the inventor. Carl Behling is the inventor

When was the patent issued? I made four or five spiral fluted 10-22 barrels in 1988. Maybe I was first and really missed out on a patent.... I also made a spiral hexadecagon barrel at the same time, a barrel with 16 spiral flats on it. Is this patented???

Sorry for this, but the idea of patenting fluting kills me!

1999 I didn't get the exact date. But hey in three more years anybody can do it. Design patents are good for fourteen years in most cases.

Again as far as a design paten goes you can patent anything that is aesthetically different. I now it's weird but it's what the USPTO says we can do.

It seem like a waste of money though

IF, flutes allow a barrel to cool faster, a spiral flute will be longer and thereby expose more surface area to cool.........

A fluted barrel is much like a "I" beam. But twist an I beam and see what happens to its strength....

No way on earth that a twisted, fluted barrel is "stiffer" that a conventionally fluted barrel......For the same number and depth of flutes

Well yes and no.

Yes a straight fluted barrel can be compared to an I beam in one way and that is material has been removed in areas that have the least effect on beam strength in one axis. Yes twisting an I beam kills nearly all it's rigidity But if you could twist a barrel from straight fluted to spiral there would be no appreciable loss of strength as we are not dealing with a square or rectangular shaped part

You are still dealing with a cylinder external grooves or not it's still a cylinder. And the grooves are not oriented to any given position on the long axis. Now if the grooves were deep enough then yes it would be flimsy as all hell but most flutes are no deeper then .125" (someone correct me if I'm wrong) With flutes that shallow and the wall thickness still pretty heavy there is little in the way of weakening the barrel. I'd be willing to bet that if you took three identical barrels one with no flutes and the other two with straight flutes and spiral flutes set them up in a vice with a dial indicator to measure deflection and hung a weight off the end I'd be willing to bet the fluted barrels would not show much difference between the two nor would it show that much difference from the non fluted barrel

quote:

Originally posted by RoyB:
IF, flutes allow a barrel to cool faster...

They don't.

quote:

But if you could twist a barrel from straight fluted to spiral there would be no appreciable loss of strength as we are not dealing with a square or rectangular shaped part

quote:

But if you could twist a barrel from straight fluted to spiral there would be no appreciable loss of strength as we are not dealing with a square or rectangular shaped part

I disagree........Lets exaggerate the fluting....Instead of a nice lazy twist, lets flute it like we are threading it...maybe 5 threads per inch......this would absolutely weaken the barrel. Now a nice lazy spiral flute might not weaken it much, but as soon as those ribs stop running right down the length of the barrel, you've lost any amount of strength they might have been adding to the barrel.
I'd bet a fair amount of $$ that if you conducted a test like you outlined you would easily see the spiral fluted barrel deflect more than a conventionally fluted barrel.

quote:

Originally posted by RoyB:

Now a nice lazy spiral flute might not weaken it much, but as soon as those ribs stop running right down the length of the barrel, you've lost any amount of strength they might have been adding to the barrel.

Flutes don't add any rigidity They reduce it

quote:

I'd bet a fair amount of $$ that if you conducted a test like you outlined you would easily see the spiral fluted barrel deflect more than a conventionally fluted barrel.

I agree but the difference would not be enough to worry about

The sole purpose of fluting is to reduce weight, then they look cool and they increase the surface area of the barrel so you may get faster cooling but since the barrel can heat up faster what's the point??

Flutes? Cooling?

Lewis Gun and Hotchkiss anybody? Didn't work then so doubt it'll work now. Was told the reason, can't remember it.

Rigidity is influenced by the 4th power of diameter/2 ( ie radius from centre.)

Its also influenced proportionately by the amount of material removed in fluting the OD section.

Fluting reduces the rigidity of the original profile slightly as it reduces weight at the same time .
The proportion of rigidity lost is significantly less than the proportion of weight lost by the fluting.

Need to talk apples & oranges with fluting.

The physical parameters mean that a rifle barrel of a given length & weight fluted is slightly more rigid than an unfluted barrel of the same length & weight.( because the fluted OD is larger).

The differences in rigidity in either situation is not something to pee your pants over .

Spiraling the fluting reduces the rigidity of a barrel of the same length & fluting depth . the influence of the fluting on rigidity is so small that the difference of the spiraling is is extremely small.In itself the influence on rigidity of spiraling the fluting is increased as the pitch of the spiraling is increased.
As the pitch of the spiraling is increased so is the amount of material removed from the barrel for the same length of barrel fluted.

But its not the weight removal that has the greatest influence on rigidity .......its a thing called "section modulus".......which is shape related.
Where the influence of spiraling has more effect on reducing the section modulus & thus rigidity than straight fluting causes.

In FEA terms ( in a cyclic pattern as you move down the barrel )the match of flute spiral to rifling direction or pitch , or otherwise, is essentially irrelevant to the influence on rigidity.

To a point increasing the surface area of the barrel increases its cooling rate..........but that is the cooling rate of the surface. The cooling rate of the barrel is limited by the heat transfer rate within the unfluted barrel cross-section under the fluting.

He He .........this is the same issue as an aluminium can supposedly cooling faster than a steel can
Yes it does , but almost negigibly , as the cooling rate of the drink in the can is limited by the rate of heat transfer rate of the contents.

The can surface initially cools quickly ......but the contents fails the "sip test" until you leave it in the fridge long enough to cool the entire contents........and the time to chill the contents itself is no different between an aluminium can & a steel can because the contents has a lower inherent heat transfer rate than either aluminium or steel.

Heat sinks work , meaningfully, with materials that have high inherent heat transfer capability & small cores with large flutes............that ain't a fluted rifle barrel, with itty bitty flutes & made from steel that doesn't exactly have sizzling heat transfer capability.( especially Stainless).

2C

Hello again,
I have called Hart barrels and they will helical flute their own barrels. They also reccomended Twisted Barrels if I was not using their barrel. I have also recieved a message from Karl Feldcamp saying that he is back up and running on the helical fluting. So it seems that there are a few people doing this.
Thanks for all the input.

quote:

Shaw has a patent on it. If anyone else is doing it they are going to get a letter from Shaw's attorney as soon as Shaw finds out about it.

A patent does nothing but prevent a commercial entity from producing a product in competition with the holder of said patent !.

So if an independent shop using a different manufactures barrel and their own set up for helical or spiral fluting said barrel ,can't be considered a patent infringement . If I were to turn a cylinder ,bore it ,rifle it and flute it regardless of shape I wouldn't be infringing on anyone's patent . I have Round cylinder Octagonal spiral cut as well as fluted drill steel from the 60's this isn't a new Idea !.

40 years ago I used to turn an flute some of that drill steel for miniature decorative working cannons , patent infringement ?. Naw don't think so !!!.

Way back when I drilled and blasted using GD Joy an IR Rotary percussive drilling equipment ,the only reason drill rod came in various shapes was to lighten the steel ,as track drilling still used Chuck Tenders ,Men who handled sections greased couplings an threaded ends with anti seize ; Then stood the sections enabling the Air hammer collar to engage another section an continue drilling or pulling out of a hole !.Empty powder bags were made into hole plugs ,until powder crew set charges an back filled them . All unnecessary personnel Cleared ,wiring charges would commence all finished area evacuated final go ahead order to blast , connect leads to charge box signal, RAM THE HANDLE butta BOOM an the earth shook and MOVED

Their patent wouldn't hold water under a decent court challenge and extremely doubtful if they would take an independent shop into court !.

Letter threats from lawyers are simply meant to intimidate without court associated cost, however subpoenas on the other hand are a different animal !.



http://www.lexic.us/definition-of/drill_steel


Composite Strengthening of Steel Structures

Standard techniques of steel structure strengthening include welding, bolting, or adhesive
bonding of steel cover plates to the existing systems. The disadvantages of these techniques
are corrosion effects, sensitivity of the repaired system to fatigue problems due to stress
concentrations produced by welding or bolting techniques, long period of service
interruption, and need of placing cumbersome frameworks. Recently, the use of epoxy-
bonded FRP materials has become a promising alternative due to its high tensile strength,
stiffness, and corrosion and fatigue resistance. However, failure of a FRP-strengthened steel
member can occur due to: (1) top flange buckling in compression, (2) web buckling in shear,
(3) FRP ruptures, and (4) debonding of FRP strips. Several studies have been conducted to
assess the feasibility of strengthening steel members using FRP composites.

Recently, the use of epoxy-bonded FRP materials has become a promising alternative due to
its high tensile strength, stiffness, and corrosion and fatigue resistance.

Now exactly how does removing barrel material " Stiffen " that barrel ?, increasing it's surface area YES it DOES . Stiffening steel by removing steel Naw don't think so !!!.

http://www.border-barrels.com/articles/bmart.htm


I Borrowed this !.


CONCLUSION ON BARREL FLUTING....

*

When comparing two barrels of equal weight, length, and material but one is solid and other is fluted, the fluted barrel will have:
o

A larger diameter
o

Greater stiffness (depending on how the extra diameter/weight is distributed)
o

Vibrate at a higher frequency (depending on how the extra diameter/ weight is distributed)
o

Less muzzle sag (depending on how the extra diameter/ weight is distributed)
*

Fluting a solid barrel will:
o

Reduce its weight
o

Reduce its stiffness
o

Increase its natural frequency of vibration Yes it Can also do that
o

Decrease its muzzle sag. Botox is generally used for that problem !
*

Reducing the weight of a barrel by fluting makes a stiffer barrel than reducing the weight by decreasing its diameter.
*
I'll buy the above statement !.

A shorter barrel of the same section, solid or fluted, will sag less and vibrate at a higher frequency.

More info on barrel dynamics...
Barrel dynamics... http://www.varmintal.com/apres.htm

One barrel maker said the main advantage of a fluted barrel was $100 more in his pocket. NOW WHY DO I BELIEVE THAT !!!.

Then we have Remington's new VTR Model

A fusion of our most advanced performance features in both tactical and varmint rifles, the Model 700™ Varmint-Tactical Rifle (VTR™) is a revolutionary system optimized for extended-range precision and mobility. Its triangular barrel contour is a product of years of rigorous research and development focused on reducing weight, enhancing rigidity and promoting rapid heat dissipation.

http://www.remington.com/produ...0/model-700-vtr.aspx

You get whatever your hearts desire ; I'll take a Schneider or Lilja ANY TIME !!!.

http://www.schneiderriflebarrels.com/ or http://www.riflebarrels.com/

quote:

Originally posted by Doc224/375:

quote:

Shaw has a patent on it. If anyone else is doing it they are going to get a letter from Shaw's attorney as soon as Shaw finds out about it.

A patent does nothing but prevent a commercial entity from producing a product in competition with the holder of said patent !.

So if an independent shop using a different manufactures barrel and their own set up for helical or spiral fluting said barrel ,can't be considered a patent infringement .

Doc I believe you are correct as far as "they won't bother to take a shop to court" but a design paten is what Shaw holds not a Utility patent. The whole purpose of a design patent is to protect an objects aesthetic design.

Its funny that you mention the money aspect of fluting. Shaw gets a patent on the fluting but fails to tell anyone that it's just a design patent and therefor by definition as no utility value or is not a new technology or process. I'd bee willing to bet they only applied for the patent to use in advertising. Once again money

Why are we worried about heat in a barrel, when we only shoot one round to kill game?? I don't understand.

quote:

Originally posted by ztreh:
Why are we worried about heat in a barrel, when we only shoot one round to kill game?? I don't understand.

Obviously you're being fatuous but varmint hunting can be a rapid fire slaughter.