Dimpled Barrel

magic647

Private
Full Member
Minuteman
Sep 24, 2010
6
8
NY
Thoughts? KAC has a dimpled barrel on their PDW, and i have recently seen it being put on their SR-15...is there really any benefit (i've heard weight reduction and increased cooling), benefit vs fluting?

Also does anyone else make them besides KAC?
 
Re: Dimpled Barrel

KAC holds a patent on the dimpled barrel IIRC. You would have to check to see if that is accurate and the extent to which their patent covers similar processes/products. Weight reduction, heat dissipation and retention of barrel stiffness/rigidity are allegedly better with a dimpled barrel versus a fluted barrel from what I have read (I'm not an engineer or otherwise scientifically-minded about such things, so I will defer to Kevin or one of the KAC guys or someone with vastly more knowledge than I).

Now, despite the KAC patent, I believe that there are companies offering barrel dimpling as a service, but again, I am not condoning or suggesting anything that might violate KAC's patent. ADCO is one such company that I can think of off the top of my head. I don't know about companies making production dimpled barrels, but again, I am not up on the subject that much as I have no need or use for one.
 
Re: Dimpled Barrel

DEZ Arms has a version that's lightly dimpled.

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Re: Dimpled Barrel

Dennis at DBMG does it. Works with high quality stuff(noveske) but will work with any. I spoke with him today and the customer service is phenomenal. I'm having a 11.25 twist, 20" LMT MWS barrel made( with dimples) in SS. He's local to me and I am impressed.
 
Re: Dimpled Barrel

If we're talking about aesthetics, I think the KAC pattern is the most attractive. The individual who came up with the pattern no longer works for KAC, but he still does the work. My friend had a Noveske barrel done about a month ago.
 
Re: Dimpled Barrel

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: TigOlBitteez</div><div class="ubbcode-body">I think the dimpling looks good and is better than a fluted barrel in terms of structure. </div></div>

Why do you say that? I think it's simply an issue of trendy looks and in fact is probably worse for structure.Remember, there are more than 1 barrel manufactures that WILL NOT flute a barrel do to induced stress.
 
Re: Dimpled Barrel

I'm just an civil engineer, no metallurgical expert o barrel maker.

From a structural point, dimpling saves weight and may keep more torsional stiffness (...for whatever it's worth, theoretically at least longitudinal stiffness is more important) than fluting after removing about the same amount of material (weight). The stresses that it may induce on the barrel are also more evenly distributed, and the round shape of the dimples avoids stress concentration. This would also vary depending on the comparative depth, number and shape of the flutes/dimples.

I have never seen any truly credible, non-biased comparison on heat dissipation, both for fluted (straight or helical) and dimpled barrels vs normal round profiles.

I would not expect any good barrel to improve accuracy wise at all by either, but probably it won't hurt if properly done unless you are talking about ultimate accuracy, where the barrel probably would be better left unmolested.

Perhaps the cut barrels will suffer less distortion after machining than other types, and theoretically the cold hammered barrels react differently (slightly contract the internal bore when you remove material on the exterior diameter) than buttoned ones (that expand = worse for accuracy). It would also depend on the type of steel, machining and heat treatment to remove residual stress, so probably it is not that easy in practice.

It might be marginally better than fluting, but it seems its use is basically looks and some weight savings...
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Re: Dimpled Barrel

I say it because it is most likely true. We are comparing dimpled or fluted. Yes there are some who will not flute barrels, but I know and have spoken with many that do. The real reason to do it is to save a little weight(though the more weight in the barrel and gun provides more accuracy, this I hope is common knowledge) The dimpling is supposedly better when compared to fluting in terms of the barrels ability to dissipate heat, and manage movement. But feel free to hate away, this is a topic which seems to have no black and white answer. Obviously not doing anything to the barrel would mean less stress to said barrel, but that was not the question.

Tiro said some good things as well in the above post.