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  • $ 17500

Barrel Flute Weight Savings Calculator

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The industry standard elevated to a fresh look with our exclusive cutter style. The finished piece emulates the appearance of a splined axle. (Depth and flute count may vary depending upon caliber, cartridge selection, and barrel contour).

"Straight with a twist." Some additional CNC code transforms the industry standard straight pattern to a whole new look. The rate of twist is almost infinitely variable. If you want to "twist it up", just tell us how much to go! (Depth and flute count may vary depending upon caliber, cartridge selection, and barrel contour)

Weight reduction.  Probably the single most asked question regarding fluting a barrel.  We recognize the need for lighter weight guns where every ounce counts.  Use our online fluting calculator above to give an approximate estimate of the amount of weight reduction you can expect from having your barrel "wrinkled up". 




We offer several distinct patterns available with 2 different cutter geometries.

Pattern "A" and Pattern "B":

Pattern "A" is a faceted shape resembling the splines on a car's axle or PTO shaft on a tractor.  It has an industrial appearance that is very popular.  The pair of 45* flanks leave a clean, but edge free finish where the flute meets the outer circumference of the bolt body.  Doing so means no razor-like edges to tear up hands and fingers.

Pattern "B" is the more conventional radial profile typical on most fluted barrels.  With a straight flute, this cutter style often leaves a razor edge, however with the spiral pattern sharp are avoided.

The difference between the two patterns is purely cosmetic.  One does not "work better" than the other so the choice is purely personal.

LRI offers fluting in 8 styles, with 2 patterns available for several of the styles.

  • "High Helix" (Pattern A or B)
  • "Standard Helix" (Pattern A or B)
  • "Straight" (Pattern A or B)
  • "Interrupted"
  • "Diamond"
  • "Wrought Iron" 
  • "Murder Hornet"
  • "Pattern X"


"Wrought Iron" barrel fluting.

We also have this pattern available for bolt fluting.  When matched it's a nice way to complete a rifle


"Murder Hornet".    A little different from the typically seen hexagon pattern.  Ours preserves the barrel contour down inside the pocket of the hexagon.  A notable difference from many competitors who use a 2 axis toolpath instead of 4 axis.






Progressive/Gain twist barrel fluting:


Few shops in the industry possess the ability to program for a progressive helical feature.  Even fewer can set it up as a variable where YOU get to decide the pattern.

LRI has this.  The challenge before us now is presenting this information in a meaningful manner.  We’ve had the machine programming process developed in house now for some time.  We’ve not made an effort to offer it because we have to develop the software interface that allows you to decide how this ultimately comes to fruition. 

Computer animation and graphics that allow you, the client, to model your own barrel online. That is the goal.

Once you settle on the pattern, that information will become stored for our machinists to use once your barrel arrives.

Were not there yet, but we are working on it and it will be available.   In the meantime we ask you to give us some artistic freedom when providing this service.


Pattern "X".

The response we've had with this pattern is nothing short of astounding.  We feel pretty confident we are the first to offer something like this.  If there are others, we haven't seen it yet.  The barrel shown had a full POUND of material removed from it.  Finished, it weighed within 3 ounces of a Proof Research carbon barrel finished at 16".  This barrel is 20".

Keep in mind it has an extra inch of cylinder length.  We can now approach the weight savings of carbon-wrapped barrels and were confident that heat dissipation exceeds because it is all one material. 

 We've performed this service to thousands of barrels using both the single point and button rifling methods of manufacturing.  It's been demonstrated over and over again that our process has no detrimental effect on accuracy.

Barrel fluting is largely cosmetic.  Because of this, we prefer our clients to allow us some "artistic freedom" with the flute count and depth.  Because of the cutter design, sometimes it's beneficial to increase or reduce the number of flutes so that the finished appearance is symmetrical.  This is one of the rare cases in machine work where "if it looks right, it is right." 


Please allow for a 2-5 week rotation on delivery


IMPORTANT NOTE:  Barrel fluting is an invasive machining process that is very, very dependent upon solid and stable work holding.  Failure to respect this fact leads to fluting work riddled with tool chatter and other inclusions.  We have a well vetted process for ensuring a visually clean appearance in our work.  However it is not without peripheral consequence.  IF your barrel is coated, blued, blasted, or "finished" in any way on the outside of it, it is very, very likely that we WILL scratch, burnish, or mark the finish.  There is absolutely no way to avoid this.  Retaining this service means LRI will not accept or be subject to any liability in any capacity.  Please take this into consideration prior to retaining us for this kind of work.  




The prices quoted for our barrel fluting services are for bolt action rifles and AR-15’s where the barrel is threaded to the receiver or contained by a barrel extension.

The full scope of possible attachment methods is outside of our scope to completely anticipate as the variances are almost infinite.   LRI reserves the right to apply additional tooling costs when the application requires it.  As always, you will be notified prior to any work being completed.  If you elect to proceed, you will be billed upon completion. Special tooling starts at $125 and up.

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