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Barrel Fluting and observation

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Barrel Fluting and observation was created by OleCowboy

Having just got back from 6 days of NRA and there are several threads on here about fluting let me pass on some observations:

Fluting is in from guns selling for $15,000 to AR's, from bbl makers like Krieger www.kriegerbarrels.com and many others. No shortage of them being employed on all makes of weapons.

I stopped by Krieger and spent some great time with one of the engineers and talked about fluting. He supports it but did add a note of caution on what is called 'Zombie fluting' This is more decorative than anything else and other than looks adds very little in fact many often significantly affect accuracy.

Here is a short article on fluting you may wish to review: www.kriegerbarrels.com/Fluting-c1246-wp3392.htm

If you are thinking of it choose an experienced and good rep company to do the work...cheap don't come good and good don't come cheap.

I am doing it to reduce the weight of my AR10T
10 years 11 months ago #23094

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Replied by faawrenchbndr on topic Barrel Fluting and observation

Weight reduction is the driving force for me, I hope to lose 5-8 ounces from the 20" barrel.

Will get a weight reduction measurement when it comes back from the machinist
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Last edit: 10 years 11 months ago by faawrenchbndr.
10 years 11 months ago #23122

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Replied by OleCowboy on topic Barrel Fluting and observation

You should lean towards the high side of that on a 20 in with full flute and for the AR10 platform fluting for weight savings is worthwhile unless you are a 20 something. I have no memories of my M 14 and basic load being heavy, but then I arms soon looked like Popeye...something to do with that daily run of 2 miles with the M 14 held over our heads and then out in front of us, repeat every 30 seconds...
10 years 11 months ago #23129

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Replied by faawrenchbndr on topic Barrel Fluting and observation

Old man time has been catching up with me lately. I'm still relatively young, 46. My "hunting" rifle is a FN SPR, she tips the sac ale a bit north of 12.5 pounds

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10 years 11 months ago #23134

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Replied by SOC on topic Barrel Fluting and observation

Here is my $0.02 on fluting.

I have seen thermal imaging of fluted barrels as they heat up. Some was footage from Accuracy International and some from 3 rd party evaluators.

The flutes DO NOT heat evenly. On a barrel the effect is the same as a bi-metal thermostat switch. Parts of the barrel heat and expand while others are cooling and contracting. The heavier the fluting the more the disparity.

IMHO if you want to save weight via lightening the barrel go to a smaller diameter. If you like the look get shallow flutes.
10 years 11 months ago #23980

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Replied by OleCowboy on topic Barrel Fluting and observation

I have read a portion of the study you are referencing by AI. That was AI in England and it was a flawed study in many ways, quality of the barrels themselves, quality of the fluting were suspect.

I have done a lot of research on this and here are some valid and undeniable take aways:

1) Fluting will result in faster cooling

2) Fluting will result in lighter weight for any given outside diameter bbl

3) Fluting MUST be done by a highly competent barrel maker or the results will be less than satisfactory. Depth, length and lands and flutes spacing MUST be precise and in harmony with the bbl being fluted. Too deep of flutes can cause issues resulting in a now too THINK bbl system.

4) Fluting will not add rigidity to the bbl vs the same bbl in OUTSIDE diameter, it will be more rigid if the inside diameter is used at the benchmark

5) some of my research led me to believe that the POI MAY change on fluted bbls as they heat up. What have not been able to find are LEGIT comapro's in fluted vs un fluted. ( a good part of my career was in R&D, Testing and instrumentation. I have not seen any test results that I would call as definitive and quantitative with proper controls)

6) You might note that Accuracy International and other high end companies that sell and market extreme accuracy still and do in fact sell 'shiper' grade rifles with standard fluted bbls

Take away: Lighter weight and faster cooling are known gains. Accuracy is far more dependent upon the quality of the fluted bbl than anything else. Drop your weapon off at Joe Chits the Ragmans Machine shop and stomach pump room and your results may not be the best.
Last edit: 10 years 10 months ago by OleCowboy.
10 years 10 months ago #24060

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Replied by SOC on topic Barrel Fluting and observation

Cool faster and also heat faster. IMHO the marginal improvement along with possible loss of preformance is not worth the cost.

As I said already unless you like the look, a smaller diameter barrel is a better and often less expensive way to shave weight.

If you want cooling wrap your barrel with a heat sink.

I am interested in carbon fiber wrapped barrels that have off axis fibers to dump heat, aid rigidity, and allow lighter weight. It has to be done right as most carbon wraps act as insilators trapping heat.

As far as I know there is only one company that offers a wrap with fibers that run from the barrel surface to the outside of the wrap instead of just around it.
10 years 10 months ago #24062

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Replied by magi on topic Barrel Fluting and observation

I've decided... For now.. I'm going to get two guns.... One cool big one and another cool light one........ I'm a simple man.......
10 years 10 months ago #24064

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Replied by OleCowboy on topic Barrel Fluting and observation

I think that is the right choice and having looked into it the price gap is just not that large,,,
The following user(s) said Thank You: magi
10 years 10 months ago #24079

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Replied by MsgtBill on topic Barrel Fluting and observation

Afternoon. My Ruger SR-762 came with a fluted barrel they say for better cooling and to lighten it, the cooling I can see but the barrel is only 16" long so how much could you lighten it ? I only wish they had a 18" or 20" option, better ballistics for the .308 WIn.
And the fluting is not much for looks since it is under for forearm . With a loaded mag the rifle weights in at 11 3/4 pounds though not designed for close quarters but it does make a good "Sniper" type rifle.
9 years 11 months ago #38466

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