Barrel fluting

[rhhudson]

Hi,

 

any one got any opinions on barrel fluting,,

 

looking at having a varmint profile with spiral fluting, is this as strong/rigid as standard straight fluting?

And despite looks is there any benefit to it?

 

thanks

Rob

[GeorgeB]

Waste of money unless you're desperate to lose weight.

[meles meles]

It's worse than just a waste of money, it's more likely to reduce your accuracy than improve it.

[Tuck]

Yeah the 2 fluted barrels Iv owned have been the most inconsistent barrels Iv had. Never again.

[Viajero]

IIRC AI did lab testing on fluted barrels , result =fail ,

 

 

http://www.longrangehunting.com/forums/f19/ai-tests-fluting-barrel-reduces-its-accuracy-147285/

[pork chop]

had a few rebarrels now every time I've discussed flutting with two different smiths and been steered away from having it done

[jcampbellsmith]

My fluted barrels shoot well but I don't plan to get any more. Mostly on the grounds of saving a bob or two. Regards JCS

[dannywayoflife]

My armalon fluted barrel is very very accurate and consistent

[mikeroz]

My 2 LW barrels are heavy varmint straight fluted. They are both super accurate. I'd hazard a guessthat they're about 25mm diameter at the muzzle, just rearward of the moderator threading.

[Viajero]

Who are we to question AI ?

[Grum87]

Plenty of rifles(AI's included) out there with fluted barrels.....

 

I question the science behind the 'test'. If you were wanting to conduct a fair test, you'd have an identical rifle and barrel, minus the flutes as a bench mark.

 

 

And you'd still find the POI for the barrel changed from shot to shot.

 

Not a good test.

[srvet]

Does the barrel making process influence if the tube should be fluted or not? Specifically, with button or hammer forged barrels is there greater potential for dimensional changes to the bore occurring when the barrel is fluted as a consequence of stressed induced within the metal.. Would this be mitigated by using a cut rifled barrels where there are less (hopefully no) stressed induced? Clearly a lot of barrel makers make a big deal about stress relieving their products. Can we be certain that this occurs uniformly?

For my 2p worth I have a Bartlein cut rifled tube that has been fluted which shoots very well!

[blaser308]

My 1 in 8 twist 243 Blaser LRS2 barrel shoots well out to 1000y and my .308 blaser barrel has shot 3 inch verticals with 185g jugs at 800y.

[ChrisF]

Maybe ? , however if you look at the old AWSM in 338LM , its barrel is thick like a truck axle & fluted , and then look at the PSR/AX 338LM , the barrel is pencil thin, its hardly apples/apples comparison .

 

Why is the AX barrel so thin, its maybe weight saving , due to all the other stuff they are hanging off the rifle , like lasers , LRF , designators & forward mounting NVG & TI etc .

[gbal]

Like many questions in rifle shooting,it's quite possible to get a fairly reliable answer to the effects of fluting on rifle precision (how well the rifle/ammo it prefers shoots). But like many questions it isn't easy.

For example,there have been about a dozen posts so far-pretty well split evenly between good and bad.

The trouble with this is clear-opinion(as much may be) and even actual firing fact will vary,but there is no systematic way to sort it out.

 

OK,option one is to conduct a large survey of users-fluted barrels-classify the barrels into categories (weight,length,calibre ,how barrel was rifled....and so on). If you can get enough feedback,then maybe some moderately reliable data might emerge...and maybe not. There are further problems to the limited sample size (we really need hundreds) and limited detail from possibly biased shooters-and vague replies (mine shoots great). It's also actually quite difficult to do-just whom do you ask (thee is np 'register' of flutees.

 

Better by far is a more 'scientific methodology';

Probably the best is to compare rifles before and after they are fluted. So shoot each rifle to provide a decent sample-say 5x5 shot groups with good control of timing etc. The repeat the testing after that barrel has been fluted. That will give a reasonable indicator for that rifle/load....but.....there are issues-

 

Fluting will reduce barrel weight (effects on heating,and general stiffness and all the other factors known to have effects-you'd-have to check if more/less than equal weight unfluted barrels..bit of both is possible!)

 

You will of course have to have quite a large sample of barrels-twenty would hardly do.

You would have to have about 20 in each of the 'categories'-how the rifling was done,barrel profiles/weights,length,calibre.....and so on....

You would also have to address a really critical issue-the fluting might alter the precision (either way) but you would have to try different ammo loads to see if the altered rifle could shoot as well as before -with a different load.....(by no means improbable,as barrrel harmonics might change-rifle mat still have the potential).

One snag is that not that many rifles are shot and carefully recorded,then get fluted and load developed again,but those that do are golden data.

 

To get really complex (but the world is complex often) you woud have to have enough data (rifles etc) to check for 'interactions'- eg light barrels are more affected by fluting,cut rifling less,fast twist more....and then three way interactions....fancy statistics do most of the work,but you need lots of data.

(if you don't think this is probable-why do you think different users report radically different findings based on their one rifle...simply put,there are likely to be a fair raft of interaction factors...that's why no one simple yes/no answer is likely.

 

OK-can we use existing rifles-those fluted and those not-well,yes we can-and can try to control factors a bit-eg use the same model rifle with same profile barrel (weight though?)...BUT rifles are not clones -even same model/calibre/barrel ones- so we need again a large sample,which helps even out such differences.

Then same shooting grouping,and some comparison should be fairly easy-within say Rem 700 PSS in 308,22 inch barrel,fluted or not.

Which is what we want..... if we optimised the ammo etc to the particular rifle.

That is a lot of work-but maybe careful sampling might reduce it-though tthen agaain ,subject to uncontrolled variables ("I did fit another trigger"/I used the old palma bullets....new palma brass...OK if you know,can sort out.)

However,if you use even careful shooter data,there may be bias.Ideally all test shooting would be blind-shooter does not know what test is about (fluting),and has no investment in the result (eg confirming his preconceptions). You might do well to have a team of 'neutral expert shooters'- under near identical conditions etc etc-there are some 'practical/logistic' issues there.

 

OK,that's an OUTLINE of the options,if you want something like a definitive answer. There is no 'theorestical' complexity,or technical (no need for complex measuring under strict lab conditions with unobtainium equipment).It's all very straightforward-just a whole lot of shooting to do,and/or expense.

ie it's in the 99% perspiration bit of reliable scientific information gathering.

 

There are a few other things to tidy up,methodologically-but it's all doable-though you can appreciate,not yet done.....nor likely anytime soon.....ad hoc user reports usually dominate-whether generally correct or not. Each such user report could be useful,of course-IF collected and categorised and so on...just isn't done-and not many 'smiths will have enough controlled data really...though some have quite a bit of 'experience',very useful if carefuly used.

 

Or you can ask a mate who used to have a fluted barrel,but do ask two,since they are statistically likely not to agree,and indeed both are probably right,for one rifle. Simples.

 

 

The AI tests seem generally well conducted (I have only seen a summary paragraph report)-of course results apply only to the model rifles rested-generalisation isn't AI's responsibilty!

Pity the actual holes on paper were not reported-they are definitive,and would be available...nor POI size reported- probably in fuller version.

Pros ans cons in their application is speculative-how many shots do snipers or hunters fire/weight saving....

 

...so yes,add 'number of shots before significant (for what purpose) POI changes occur' in all the above data collection and analysis.

 

gbal

[Murph]

My 1 in 8 twist 243 Blaser LRS2 barrel shoots well out to 1000y and my .308 blaser barrel has shot 3 inch verticals with 185g jugs at 800y.

My Lrs2 in 223 has a fluted barrel also. It very rarely heats up. The moderator is always much hotter than the barrel.

[Swarovski1]

My armalon fluted barrel is very very accurate and consistent

my 6.5 06 is an armalon deep fluted barrel.not sure if the bigger surface area thing really makes any difference but it loses well over 1 lb of metal being fluted.they look very good too.best I've seen.

[Berserk]

Ive had a few rifles with fluting and have to say they look better, save abit of weight albeit very minor.

 

Of the rifles I had fluted have all been as accurate as anything else without flutes so I could not say they are any more or less accurate.

 

I have to say that my next rifle will be fluted.