Fluting effect on accuracy

[GoFightNguyen]

There's a lot of opinions (read: superstition) about barrel harmonics and exactly what does or does not affect accuracy. Barrel length vs velocity is pretty well sorted and measurable. My bartlein blank for my first precision rifle is at the machine shop right now. I want to shoot PRS with it, but I suck at shooting offhand, and would like a lighter barrel without sacrificing accuracy. Is a fluted barrel going to negatively affect accuracy? It must heat up faster, given the mass reduction....

 

[_Windrider_]

There's a lot of opinions (read: superstition) about barrel harmonics and exactly what does or does not affect accuracy. Barrel length vs velocity is pretty well sorted and measurable. My bartlein blank for my first precision rifle is at the machine shop right now. I want to shoot PRS with it, but I suck at shooting offhand, and would like a lighter barrel without sacrificing accuracy. Is a fluted barrel going to negatively affect accuracy? It must heat up faster, given the mass reduction....

Some say it cools faster because of the increased surface area. Most experts agree it’s an astethics only thing. They are just as accurate as non fluted. You just have to find what works for that barrel. If you reload do workups. If you don’t you have to try different factory loads u til you find what it likes best.

 

[GoFightNguyen]

In my opinion, such a comparison between 2 separate barrels will only prove that one barrel is more accurate then the other. Which one is fluted will be a hypothetical. I've yet to have 2 barrels that were capable of equal accuracy levels.

On the other hand, if 5 barrels of each were used in a comparison, all of equal contour and length, all being chambered with the same reamer and fitted to and fired from the same action, then a probable statistic could be achieved.

Good conversation....

Don't you try sweet talking me with statistically significant populations! While I agree with your point, I think it's worth being realistic about it. If one of the two barrels is outrageously more accurate across a string of shots, then it's probably safe to say it's better. If the two are close, then fluting or not if probably irrelevant.

One one hand, fluting adds structural rigidity, like an I-beam. On the other it provides less mass for heat soak, and therefore heats up faster while shooting a course of fire. Then again, maybe the increased surface area allows better cooling, so the barrel reaches thermal equilibrium faster.

For a cold bore shot, I bet they make no difference. I think the benefit gained from increased accuracy while shooting offhand will outweigh the heat soaking aspect. But I have no idea. Flutes also look cool.

 

[mdmp5]

One one hand, fluting adds structural rigidity, like an I-beam. On the other it provides less mass for heat soak, and therefore heats up faster while shooting a course of fire. Then again, maybe the increased surface area allows better cooling, so the barrel reaches thermal equilibrium faster.

Fluting does not add stability. You are removing material when fluting a barrel, not manufacturing a fluted shape with an equal amount of starting material as a regular barrel. A 6 lb 24” fluted barrel is stronger than a 6 lb 24” non fluted barrel. However, starting with a 6 lb 24” barrel and removing a lb of material will not make it stronger. It is a misunderstood concept that has been explained poorly over the years, especially by shitty gun store salesmen

 

[Geno C.]

I took a 30" 1.25" straight barrel and had it chambered in 6br. Worked up a load that was pretty consistently 1/4moa. Sent it to Paul over at PPR and had vortex fluting done, lots of meat taken off. It didn't shoot the same load as well but I tweaked it a little and it shot every bit as well as before fluting

 

[OLD308]

Look up the test Shilen, Lother Walter, and Sako did on the effects of fluting. There is a reason TRGs don’t come fluted anymore. I have fluted guns and non fluted. Both shoot just as good. But the science says that there is an increased risk of accuracy loss by fluting a barrel. Ridigity is a non issue with short heavy barrels. Fluting for cooling is BS on a bolt gun. Weight savings is a joke. Look it up, the experiments/test by the manufacturers are published.

 

[quietmike]

Fluting adds cost to what is essentially a disposable product.

 

[GoFightNguyen]

Fluting adds cost to what is essentially a disposable product.

Sure, we're all here because we've proven that we're willing to spend money on a disposable product.

 

[Kopfjager1]

Mijp5 is correct.
A barrel that has been fluted after the bore has been drilled and rifled, will relieve stresses and has the potential to create "potholes" in the bore later on in it's barrel life, increasing uneven wear in the bore, affecting accuracy and overall precision.
While weight savings on the barrel alone are a joke, having every part possible, milled to reduce weight, it will make a difference.
Surface area doesn't really matter when it comes to cooling a barrel down, what does matter, is the distance from the bore to the exterior. While larger outer diameter barrels take longer to heat up/cool down compared to smaller profile barrels, it also takes more heat for it to transfer through the steel to reach the same exterior temperature as a smaller profile barr. This means the bore is significantly hotter in the larger profile barrel.

 

[Geno C.]

Mijp5 is correct.
A barrel that has been fluted after the bore has been drilled and rifled, will relieve stresses and has the potential to create "potholes" in the bore later on in it's barrel life, increasing uneven wear in the bore, affecting accuracy and overall precision.
While weight savings on the barrel alone are a joke, having every part possible, milled to reduce weight, it will make a difference.
Surface area doesn't really matter when it comes to cooling a barrel down, what does matter, is the distance from the bore to the exterior. While larger outer diameter barrels take longer to heat up/cool down compared to smaller profile barrels, it also takes more heat for it to transfer through the steel to reach the same exterior temperature as a smaller profile barr. This means the bore is significantly hotter in the larger profile barrel.

I don't believe your last sentence is correct. A larger profile will have more steel to dissipate the heat. More mass to even out the temp. It will maintain bore temp longer than a light one but it will not be hotter.