Fluted heavy barrel- question

[redneck2]

I have a custom .358 WSSM upper on my AR that I use for deer hunting. Shilen Ultra Match blank IIRC. When I asked the gunsmith how much weight fluting saved, he paused and said "no one has ever asked"

He weighed one that was fluted, one plain. Saved half a pound on my rifle. It's a bull barrel and real heavy anyway, so the weight saving was worth it to me.

FWIW, mine shoots three shot groups in the .4's

I also have a Weatherby in .243 that has a fluted barrel. On that rifle, I really don't care one way or another. That's the way it came so that's what I use.

 

[MistWolf]

...as to the quicker cooling, I have found it to be so miniscule as to not really be a factor...

Compared to what? A round barrel of the same length and same mass? Or a round barrel of the same length and greater mass? Or...?

 

[USSR]

Compared to what? A round barrel of the same length and same mass? Or a round barrel of the same length and greater mass? Or...?

Just in general with all the other guy's rifles on the firing line. It's not like my rifle barrel was cooling down way faster than anyone else's on the line. If you want to flute a barrel solely for that reason, you will be disappointed.

Don

 

[MistWolf]

A fluted barrel of the same length, mass and material as a round barrel will cool faster as it has more surface to radiate heat. That' why they put cooling fins on your radiator instead of just using plain tubing. It's physics

 

[Clint M]

The theory of faster cooling of a fluted barrel is increased surface area, and that's all it is. If one is seeking a way to cool faster and not look cooler then one would choose a really matte finish heavy matte that creates as much surface area as possible. It's been a few years since I researched all of this, and you will see very few fluted barrels on short range BR. Fluting comes down to buyer/owner preference, if you like fluting I can't see a reason not to have it in todays market.

If you are trying to prove fluting makes a difference in accuracy of either potential from barrel, or if it will surpass shooters needs then I suggest researching, as there are in depth articles researched, and documentation from barrel makers to people testing.

 

[jmr40]

the weight savings are miniscule.

Saved half a pound on my rifle. It's a bull barrel and real heavy anyway, so the weight saving was worth it to me.

I saved 6 oz on my Winchester sporter weight rifle.

On a rifle, those are significant weight savings especially when there is no loss in accuracy.

 

[scythefwd]

Clint.. I could picture it having a place if you needed to shave a few oz to keep it under heavy bench rest weight...

Wonder if a knurled barrel would cool faster than a matte barrel?? If nothing else, it would look wicked

 

[Clint M]

jmr40 I agree with you if 6oz makes a difference in the application you are presented with I see no reason not to have a fluted barrel, and in today's market prices, choices etc I say get what you want. If I wanted a fluted barrel, and I were purchasing a new custom barrel for a hunting rifle I would buy it with the flutes already cut, and give the barrel manufacture the job of cutting the flutes. On a second hand barrel I wouldn't worry to much if I just had $100 in a barrel, but has anyone notice the prices on new "on the list" barrel makers prices ? and they have waiting list as well. All that said the additional cost of fluting a barrel can be expensive for the return. I have seen some premade barrels that fluting did not seem to add much cost to at the same time. Benchrest people live in another world LOL, I have tried getting there, but the travel is to far. I plan to shoot BR before my days are over, with the cost of custom everything if I was ordering a barrel I would have a known weight before doing so. At $500 plus for a barrel blank I don't want to worry about going over in a Light Varmint.

Knurling can/will also add surface area, and will also add to the final diameter. Different types of knurling (cut knurling, pressed etc)would be different, however I think I have seen knurled barrels before. The 10/22 crowd used to have pretty good barrels in .920 for around $80 in stainless, lots of bling has been performed or attempted on the barrels.

 

[Nature Boy]

What if you put fins on it?

 

[Vern Humphrey]

That's been done, too -- the M1921 and M1928 Thompson SMGs had finned barrels.

 

[Clint M]

Fins like that would be great for some water to cool with. Of all the barrel finishes I have owned in 223 rem ( I shoot the most target with) I keep a small igloo cooler with water ice half full or more, a wet rag or 3 and use that wrapped around, and laid over barrel. It's the only thing I have found to cool a barrel enough to get back to shooting sooner, stainless is great using this, but have used on blued, painted as well..... if blued put some rust protection on before leaving range.

 

[1911 guy]

I posted stiffness, weight and cooling right of the bat, everyone started questioning the hows' and whys'.

If you have two barrels of equal diameter, one is fluted and one is not, it is simple physics. The fluted barrel weighs less, is stiffer and cools faster than the unfluted (although all these variables depend on diameter and geometry of fluting)

Accuracy is a whole different ballgame and there are no "simple" answers. Barrel harmonics plays a large role and changing the weight, mass and shape of a barrel affects that greatly. If I had a decent shooting barrel, there's no way I'd have it fluted. While there is a chance harmonics may be improved, there's also equal chance they'll degraded.

 

[Vern Humphrey]

I have used an ordinary small kitchen funnel and a length of plastic tubing to run water down the bore, followed by a dry patch.

 

[USSR]

A fluted barrel of the same length, mass and material as a round barrel will cool faster as it has more surface to radiate heat. That' why they put cooling fins on your radiator instead of just using plain tubing. It's physics

Yeah, it's physics. But if a round barrel takes 15 minutes to cool .vs 14 minutes for a fluted one, as I said, you will be disappointed if that's the only reason you fluted your barrel. The big numbers simply are not there for "rapid cooling".

Don

 

[Clint M]

USSR same results here, matter of fact I could tell no difference in cooling at all, however I'm sure there is some minor difference. Water down barrel method has ended up with action full of water, I found the wet rags easier. I think a better fitting tube would not have that problem I may try it again as I had a pretty warm 223 barrel a couple days ago. Glad this thread popped up I have a project now in mind for water down the barrel.

 

[bush3755]

Fluting a barrel removes strips of metal that subtract fom whatever resistance to bending it had. There's less material to resist expanding on the outside curve of a bent barrel and compressing on the inside one.

You can't violate the laws of simple physics. Fluted barrels are less stiff then before they're fluted. Ask a mechanical engineer working with material rigidity and flexibility.

http://www.snipercountry.com/articles/realbenefitsbarrelfluting.asp

Fluting button or forged rifled barrels changes the bore diameters unevenly under the flutes. So says gunsmiths who've gauged them before and afterwords. Minimal or no bore diameter changes with cut rifled ones; if they've been properly stress relieved.

Barrel temperature is harmless to accuracy or changing point of bullet impact if it's properly stress relieved and fit to the receiver.

 

[HexHead]

Those are secondary benefits.

The primary benefit is they are cooler looking and cost more then non-fluted barrels!!

Rc

Yep. On a Blaser, the fluted barrel adds $1000 to the price.

 

[Blade First]

"The fluted barrel weighs less, is stiffer..."

This myth deserves to die once and for all. A fluted barrel that is the same diameter as an unfluted barrel is not stiffer...it is less stiff because of the material removed.

Don't be afraid to let common sense intrude on the thought process.

 

[Dr.Rob]

I have two rifles with fluted barrels, both are bull profile so there was significant weight savings. Both were manufactured that way, both are very accurate.

I can't tell much difference in heat dissipation.

 

[MistWolf]

...If you have two barrels of equal diameter, one is fluted and one is not, it is simple physics. The fluted barrel weighs less, is stiffer...

Not so

...Fluted barrels are less stiff...

Not quite

From Varmint Al's website (who is an engineer)
http://varmintal.com/aflut.htm

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:

-A larger diameter

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

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

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

Fluting a solid barrel will:

-Reduce its weight

-Reduce its stiffness

-Increase its natural frequency of vibration

-Decrease its muzzle sag.

Reducing the weight of a barrel by fluting makes a stiffer barrel than reducing the weight by decreasing its diameter.

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

 

[Deus Machina]

Oh, and on the matter of weight savings and aid in cooling, that completely depends on the design.
A lot of companies will do cosmetic milling, almost purely for looks. This is probably by far the most common style on anything off the shelf. Probably no notable aid in cooling and a very minor dip in the weight, which may or may not be noticeable depending on the rifle. It is all up front, after all.
Fluting done specifically for the benefits is obviously going to benefit more. These will have more flutes, wider flutes, and notably deeper flutes, enough to actually increase surface area.
And mostly trying to keep the most bulk where they need it and keep the weight to manageable levels.

 

[bush3755]

Cooling; something most barrels don't need if they're fit right to the receiver. Starting with a cold barrel, 40 shots 15 to 20 seconds apart inside 2 inches at 600 yards from a Hart barreled Win 70 as tested by a Nat'l champion. Few, if any, commercial rifles are built that way; they string shots as their barrel heats up. Why do you think accuracy guarantees are for only a few shots?

Have your receiver face squared up to its tenon thread axis then shimmed .001" less than what was faced off so the barrel clocks back to the witness mark and the same headspace. If the barrel is well stress relieved, it probably won't walk shots as it heats up.

 

[jmr40]

You know, original rifle barrels were octagon shaped because manufacturing methods of the day made them easier to produce. Making them round was done later to decrease weight with no noticeable difference in accuracy. Traditionally if someone wanted a lighter gun they just turned the barrel down to a smaller diameter on a lathe, or made them shorter. But at the cost of less performance and accuracy. Cutting flutes in them is just the next step in the evolution of trying to get a lighter gun that still had the accuracy potential of heavier barreled guns.

About cooling. In theory it works,that is science. The greater the surface area the faster something will cool. But in practice, I've never noted enough difference to matter.

Some guys still want to keep doing stuff they same way it was done in the 1700's. There really have been some advancements in firearms and most actually work. Fluting barrels is just one example.

 

[bush3755]

I don't think barrel weight alone has any effect on the accuracy it will shoot bullets at. Hand held rifles that are heavier (within limits) are easier to hold steady, but from return to battery test fixtures holding them in repeatable point of aim, heavy barrels with the same length and twist shoot with equal accuracy. They each have repeatable, but not identical, movements while the bullets goes through the barrel.

 

[Sunray]

Fluting does nothing but add decoration. Weight change is negligible. Doesn't stiffen squat or add enough surface area to make the least bit of difference.
"...saw one fluting job that cut 14 ounces..." On what diameter/length barrel? 14 ounces is a great deal of cutting.