Fluted Rifle Barrels

[joed]

How much weight does a fluted barrel save? I've always wondered about this.

I had a Savage 12 VSS that came with a fluted barrel, the worst accuracy I ever got out of a heavy barreled rifle. No matter what I tried it just strung shots vertically. Ended up selling it because I couldn't get it to improve.

So I'm also wondering about accuracy with fluted barrels. I've tried to stay away from them just because of the one bad experience.

 

[kis2]

I don't know exactly how much weight, but a fluted barrel obviously weighs less than a nonflute of the same profile and diameter. A few ounces here and there can shave a pound off a rifle.

IMO, to really see the gain in a fluted barrel, you have to compare barrels (fluted vs non) of the same weight, not diameter. A fluted barrel of the same weight as a non will likely be stiffer.

In a quality barrel, flutes shouldn't make a difference in accuracy. Again, what flutes allow me to do is have a stiffer barrel that weighs the same as a smaller diameter (less stiff) barrel.

Worth the extra cost? I don't know, depends on your purpose I suppose. But don't let one bad experience turn you off.

 

[Ramone]

off the top of my head, about 20%- and I *think* they stiffen it a bit.

Sad to hear about your mod12- I have a 12BVSS that's good for 3/4 MOA all day long (if I am).

 

[45_auto]

Flutes have nothing to do with stiffening a barrel. They reduce the stiffness when compared to a barrel of the same diameter by reducing the barrel OD in the fluted area.

Stiffness of a tube is determined by the second moment of inertia, where the outside diameter of the barrel is raised to the 4th power: I = (pi * (OD^4 - ID^4)) / 64

A fluted barrel can possibly be stiffer than a barrel of the same WEIGHT, because you could make the fluted barrel diameter bigger using the weight you saved in the flutes to increase the diameter. That OD raised to the 4th power makes a huge difference in stiffness.

Given two barrels of the same diameter, one with flutes and one without, the solid one will be stiffer and heavier, and the fluted one will be more flexible but lighter.

 

[joed]

I tried and tried with that Savage but the target looked like the right side of the letter "V". Don't know if it was a bad barrel or not but the gun just refused to stop stringing shots and I fooled with the bedding quite a bit.

The place that builds my rifles when asked about a brand will say "There are ****, and there are ****", meaning some shoot, some don't. They've told me this same thing about Remington, Winchester and Savage. They also told me what to try on the Savage to fix it.

I replaced the Savage with a Remington 700 that just clearly outshot it. A real shame for what the Savage cost. My other Savage, a 10fp was the most accurate rifle I ever owned.

But I've wondered about fluted barrels ever since. In fact I passed on another rifle because of it.

 

[joed]

Given two barrels of the same diameter, one with flutes and one without, the solid one will be stiffer and heavier, and the fluted one will be more flexible but lighter.

That was pretty much what I figured. The fluted barrel I had was no better then the sporter barreled bolt actions I owned.

 

[helotaxi]

What stock did you have on the VSS?

 

[USSR]

How much weight does a fluted barrel save? I've always wondered about this.

I had a Savage 12 VSS that came with a fluted barrel, the worst accuracy I ever got out of a heavy barreled rifle. No matter what I tried it just strung shots vertically. Ended up selling it because I couldn't get it to improve.

So I'm also wondering about accuracy with fluted barrels. I've tried to stay away from them just because of the one bad experience.

joed,

Depending upon the barrel contour and length, figure between 1/2 and 1 pound. Regarding the problem with the fluted barrel on your Savage, I would only have fluting on a barrel that was cut rifled, in which the fluting is done PRIOR to being reamed and rifled, which is not the case on button rifled barrels such as Savage uses.

Don

 

[Art Eatman]

Stringing of shots is quite often a problem with the forearm bedding. The steel heats up faster than the wood or fiberglass and the result is a change in pressure against the barrel. The change in pressure creates a change in barrel harmonics.

My common solution--assuming that's the problem--has been to free-float the barrel and then put a low-pressure shim at the forearm tip. Maybe a five-pound pull of separation to get the shim into place. Not much pressure, anyway. The shim acts as a damper.

Fluting? Yeah, for equal weight fluted is stiffer. For equal diameter, fluted is lighter. One justification is a faster cool-down during shooting. Other than anecdotal stories favoring or objecting, I know of no definitive, "It's wonderful!" or, "It's horrible!" data.

 

[joed]

What stock did you have on the VSS?

helotaxi, it was a Choate stock. Very stiff but a pain to carry which was another reason I sold the rifle. That barrel was free floated extremely well too. I know, I had it apart more times then I care to count. After 4 months of fooling with it I just couldn't get it to stop stringing the shots.

Doesn't surprise me about what USSR mentioned as I remember running across that while looking for info.

It was a beautiful rifle and not cheap. You can see the target, 2 holes touching, the rest just went up like the right side of a "V". Probably shot that group 20 times before giving up.

 

[Vern Humphrey]

To my way of thinking, fluted barrels are like other gun fads -- I regard them like tattoos on a women, she may be cute today, but forty years from now it'll be a different story.

 

[helotaxi]

Fluting increases surface area which aids in cooling, however the removal of material means that the barrel heats faster compared to the same . The overall result is a wash with regard to heating comparing the same barrel with and without fluting.

 

[helotaxi]

Did you ever give it a try without the super tall bi-pod, like from a rest and rear bag?

 

[joed]

Did you ever give it a try without the super tall bi-pod, like from a rest and rear bag?

Tried sandbags and my rest, plus 3 different scopes and a lot of shimming of the action. It never stopped the vertical stringing. You could duplicate that target every 5 shots.

And that was chambered in .22-250. If it could have just stayed with the first 2 shots it would still be in the safe now.

In my heart I believe it was the fluted barrel, I tried every trick I knew and some my gun builder gave me. The place that builds my rifles told me Savage is an excellent rifle, but there are some that slip through that will not shoot. And he says this about every make having bad ones.

 

[wingman]

I have 3 fluted barrels, 2 savage, 1 Thompson center all three very accurate don't see how fluting could cause an accuracy problem IMO your problem with the Savage was bedding or scope.

 

[lightman]

I have to agree with wingman.It may have been the barrel,stock,scope,or scope mounts.But the flutes were not the problem.All of my custom barrel varmint rifles have fluted barrels,and they shoot great.The pros and cons of flutes can be argued,but I just like the way that they look.There is a lot of good info on Varmint Al's web site on fluted barrels,well worth the time to look. Lightman

 

[MCMXI]

don't see how fluting could cause an accuracy problem

Poorly executed fluting can cause accuracy problems. As the barrel heats up, if the residual stresses in the barrel are uneven, the barrel may warp in one particular direction.

To my way of thinking, fluted barrels are like other gun fads -- I regard them like tattoos on a women, she may be cute today, but forty years from now it'll be a different story

Quite a few rifle makers who's products are used for "serious" work use fluted barrels so I don't agree with this statement. They're here to stay.

 

[shinz]

I don't pretend to know much about barrel making but I've thought about barrel fluting & wondered if how it is done would make a difference, Milling flutes in one cut would tend to release stresses contained in the barrel unevenly, so too would milling them sequentially around the barrel. To my simple mind, its a job that would want doing in a series of light cuts & indexing the barrell such that as far as possible, each next cut is opposite to the previous one. A button rifled barerel would need stress relieving before & maybe after such milling to nullify the effects of barrel heating on the inherent stresses all these processes impart. I think.
Steve.

 

[interlock]

fluting looks really cool

 

[Canazes9]

Odd, I seem to see a lot of replies emphatically stating that a fluted barrel has no performance advantages (and actually has disadvantages) compared to a non fluted barrel of the same diameter while ignoring the weight discrepancy between the two.

Do some of you actually build a rifle this way? Barrel can only be made a maximum taper of XXX. Weight? Oh that doesn't matter at all.....

If you set a "budget" for max weight on the barrel, pick a length, pick a material then compare identical barrels of equal weight except for fluting vs non fluting, the fluted barrel will always be stiffer and dissipate heat more effectively than a non fluted barrel of the same weight. The fluted barrel of the same weight will be a larger diameter.

Exceptions to this will be ultralight mountain rifles and rifles where weight doesn't matter and you can shoot the heaviest barrel available. Everything in the middle will have improved performance from a fluted barrel all other factors being equal. Obviously if you pick barrels based on maximum diameter/taper profile and don't factor the weight in at all then the fluted barrel will not perform as well as an unfluted barrel.

I don't understand why anyone would do that......????

David

 

[Walkalong]

A fluted barrel can be seriously accurate, and it can be inaccurate, just the same as a non fluted barrel.

And as pointed out, it may not be the barrels fault.

How much weight does it save? USSR answered that.

 

[joed]

I still think I was right to stay away from a fluted barrel. All I can say from my experience was that Savage barrel would change POI as it became warm. Look at the target and you can see how shots just walked up the right side of a "V". If I let it cool it would just duplicate that target every time. There were no bedding issues either.

My guess is there is a lot of truth to the statement about button riflling and fluting. I'd never own another fluted barrel.

 

[Jim Watson]

Gale McMillan (Mr no need to break in a barrel.) said the main function of barrel fluting was to move $50 from your pocket to the machinist's.

 

[Maverick223]

My common solution--assuming that's the problem--has been to free-float the barrel and then put a low-pressure shim at the forearm tip. Maybe a five-pound pull of separation to get the shim into place. Not much pressure, anyway. The shim acts as a damper.

That is good solid advice. I prefer to simply bed it and add about 5lbs of downward pressure while it cures (gives you 5lb of upward pressure after curing), which is a fairly similar (albeit more difficult) process.

Poorly executed fluting can cause accuracy problems. As the barrel heats up, if the residual stresses in the barrel are uneven, the barrel may warp in one particular direction.

Exactly. A good barrel is paramount, fluted or not...I imagine that joed just happened to be the unlucky guy that received a bad one, and fluting did it no favors.

That said, I like fluting (on a good barrel) as it increases stiffness and surface area for a given weight. Greater stiffness yields less droop, and greater surface area (with the same capacitance) yields better radiant properties, so it heats up slower (or rather: expels heat more quickly).

Gale McMillan (Mr no need to break in a barrel.) said the main function of barrel fluting was to move $50 from your pocket to the machinist's.

Wouldn't be the first time he was wrong.

 

[jmr40]

I have some of both. I see no gains in performance, but I see a bit of weight reduction, with no loss in performance over heavier non-fluted barrels.

The exact weight loss is hard to predict because of so many variables, but I'd estimate around 4-5 oz on a 24" heavy barrel. My Winchester Extreme Weather rifle with a fluted barrel weighs about the same as a comparable Winchester Featherweight even though the FW has a thinner barrel.

If weight is a concern they are worth it to me. You get the weight loss, without sacraficing performance.